This Keto Chocolate Peanut Butter Cake is over-the-top delicious. Three layers of tender low carb chocolate cake with sugar-free peanut butter frosting and a rich chocolate glaze. It’s a peanut butter lover’s dream!
Allow me to introduce myself. My name is Carolyn and I have an all-consuming obsession with chocolate and peanut butter. It’s genetic and I’m pretty sure I’ve had this condition since birth.
It’s actually a very common affliction that affects many people worldwide. Chances are good that you have it too! Otherwise you probably wouldn’t even be reading this post.
You know the best cure for this affliction? Cake. A really amazing cake that tastes like eating keto peanut butter cups. Keto Chocolate Peanut Butter Cake is almost always the answer, no matter what the question!
If this flavor combo is your obsession, be sure to check out my Keto Peanut Butter Balls too.
You will love this cake!
I originally dreamed up this beautiful Keto Chocolate Peanut Butter Cake back in 2014. It was delicious back then but my keto baking skills have vastly improved and I decided it needed an update.
I made the cake similarly to my Keto Devil’s Food Cake, as it’s so wonderful and chocolatey. I also re-vamped peanut butter frosting by folding in whipped cream to give it lightness and structure. It was both airy and luscious, and reminiscent to Keto Peanut Butter Mousse.
Finally, I created a chocolate glaze to decorate the cake. It was the perfect consistency to drip down the sides decoratively.
The final cake is just as delicious as the original, but with even fewer carbs! It’s definitely worthy of all your special occasions.
Ingredients you need
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- Almond flour: Make sure to use a good finely ground almond flour for the best cake texture. You can also use sunflower seed flour for a nut-free version.
- Sweetener: I used granular Swerve in the cake and powdered Swerve in the frosting and glaze. I also used a little allulose in the glaze to keep it shiny and soft. See the Expert Tips section for other sweetener options.
- Cocoa powder: If you want a dark chocolate cake, use dark cocoa powder.
- Protein powder: Added dry protein like whey protein powder gives keto cakes a lighter texture and more structure. I don’t recommend skipping it, although you can also use egg white or plant-based protein. Do not use collagen as it will make the cakes gummy and hard to cook through.
- Sour cream: Full fat sour cream adds wonderful tenderness to keto cakes and muffins.
- Peanut butter: Any creamy natural peanut butter should work for the frosting. I really like the Santa Cruz brand.
- Cream cheese: Cream cheese gives the frosting more structure without having to add copious amounts of powdered sweetener.
- Whipping cream: Folding whipped cream into the frosting gives it a luscious mousse-like texture.
- Unsweetened chocolate: The chocolate drip glaze really is the perfect finish to a cake like this. Unsweetened chocolate is not the same thing as sugar-free chocolate like ChocZero or Lily’s. Those have been sweetened already.
- Kitchen staples: Eggs, butter, baking powder, vanilla, salt.
Step by Step Directions
1. Prepare the batter: In a medium bowl, whisk together the almond flour, sweetener, cocoa powder, protein powder, baking powder, and salt. Stir in the sour cream, eggs, and vanilla. Stir in the water one tablespoon at a time until the batter is thick but pourable.
2. Bake the layers: Divide batter evenly among 3 greased 8-inch cake pans and bake at 325ºF for 15 to 20 minutes, or until just firm to the touch. Remove and let cool completely in the pans.
3. Prepare the frosting: In a large bowl, beat the peanut butter, cream cheese, and butter together until very smooth, about 2 minutes. Beat in the sweetener and vanilla extract. In a separate bowl, whip the cream until it holds stiff peaks. Fold into the peanut butter mixture until no streaks remain.
4. Frost the cake: Place one layer of cake on a serving platter and spread with about one quarter of the frosting. Top with another layer of cake and another quarter of the frosting. Add the remaining layer of cake and spread the top and sides with the remaining frosting. Refrigerate for one hour to firm up.
5. Prepare the glaze: In a small saucepan over medium heat, bring the cream to a simmer. Remove from heat and add the chopped chocolate. Let sit a few minutes to melt. Add the sweeteners and whisk to combine. Let cool a few minutes to thicken.
6. Decorate the cake: Drizzle the glaze over the top of the cake along the edges, letting it drip down the sides. Smooth the remaining glaze over the top of the cake. Top with keto peanut butter cups and sprinkles, if desired.
Expert tips
Always make sure to prep your cake pans properly. This includes greasing the pan and lining them with parchment paper circles. And then greasing the parchment as well. This ensures that your cakes flip easily out of the pans.
Don’t overbake those cake layers! It’s easy to do and they will end up dry. I touch the tops of my cakes multiple times during baking. The minute they feel dry on top with a little bounce underneath, I get them out of the oven. Watch my video for the Best Tips on Baking Keto Cakes.
Sweetener Options
You can use almost any granular sweetener in the cake layers, but the baking time may change so keep your eye on them. Additionally, any confectioners-style sweetener should work in the frosting. I do find that allulose can make things a little softer so allow it to firm up properly in the fridge before adding the glaze.
Frequently Asked Questions
Not all peanut butter is created equal. Some of the commercial brands are highly processed and full of sugar and preservatives. But natural peanut butter that has no added sugar has only about 5 to 6 grams of carbs per 2 tablespoon serving. Most people find they can use it sparingly on a keto diet without issue.
Keto friendly cake like this Chocolate Peanut Butter Cake is made with alternative flours and sweeteners. In this case, almond flour forms the base of the cake, along with protein powder and sweetener.
If you want to prepare this keto cake ahead, make the cake up to the point of adding the chocolate glaze. Then wrap carefully and refrigerate for up to 5 days. Add the glaze a few hours before serving.
Keto Chocolate Peanut Butter Cake
Equipment
- 3 8-inch metal baking pans
Ingredients
Cake
- 2 cups almond flour
- ¾ cup Swerve Sweetener or other granular sweetener
- 6 tablespoon dark cocoa powder or Dutch process
- ⅓ cup unflavoured whey protein powder or egg white protein powder
- 2 ½ teaspoon baking powder
- ½ teaspoon salt
- ½ cup sour cream softened
- 3 large eggs
- 1 teaspoon vanilla extract
- 2 to 4 tablespoon water
Peanut Butter Frosting
- ¾ cup creamy peanut butter
- 4 ounces cream cheese softened
- ½ cup butter softened
- ¾ cup Swerve Confectioners or other powdered sweetener
- 1 teaspoon vanilla extract
- ¾ cup heavy whipping cream
Chocolate Glaze
- ¼ cup heavy whipping cream
- 1 oz unsweetened chocolate chopped
- 1 tablespoon Swerve Confectioners
- 1 tablespoon allulose granular
Instructions
Cake
- Preheat oven to 325ºF and grease three 8-inch round cake pans well. Line the bottom of the pans with circles of parchment and grease the parchment.
- In a medium bowl, whisk together the almond flour, sweetener, cocoa powder, protein powder, baking powder, and salt.
- Stir in the sour cream, eggs, and vanilla. Stir in the water one tablespoon at a time until the batter is thick but pourable.
- Divide batter evenly among prepared cake pans and bake 15 to 20 minutes, or until just firm to the touch.
- Remove and let cool completely in the pans.
Peanut Butter Frosting
- In a large bowl, beat the peanut butter, cream cheese, and butter together until very smooth, about 2 minutes. Beat in the sweetener and vanilla extract.
- In a separate bowl, whip the cream until it holds stiff peaks. Fold into the peanut butter mixture until no streaks remain.
To Assemble
- Place one layer of cake on a serving platter and spread with about one quarter of the frosting. Top with another layer of cake and another quarter of the frosting.
- Add the remaining layer of cake and spread the top and sides with the remaining frosting. Refrigerate for one hour to firm up.
Chocolate Glaze
- In a small saucepan over medium heat, bring the cream to a simmer. Remove from heat and add the chopped chocolate. Let sit a few minutes to melt.
- Add the sweeteners and whisk to combine. Let cool a few minutes to thicken, and then slowly drizzle over the top of the cake along the edges, letting it drip down the sides.
- Smooth the remaining glaze over the top of the cake. Top with keto peanut butter cups and sprinkles, if desired.
Billie Theed says
My husband made this came for me as a surprise for Valentine’s day. It was amazing. I couldn’t believe how wonderful it tasted. Thank you so much for posting all of these recipes. It has made the difference in my weight loss. I am 60 lbs down and you have really helped to make that happen.
Carolyn says
I am so glad and go husband for making this!
Melissa says
This cake is phenomenal! I made it yesterday for my husband’s birthday and he agrees! I sifted my dry ingredients beforehand and used the baking soda/apple cider vinegar/cream of tartar and the texture and moisture was just fantastic. Great flavor. I served it to some non-low-carbers and they couldn’t believe it was sugar and grain free. Excellent job, Carolyn!!
Sally says
Can I use unsweetened cocoa powder, on the container it has a conversion of 3 tbls of cocoa with 1 of oil for each ounce. If so, do I use both oil and then add the butter in the recipe. Do not have the bar chocolate and unable to get out. Lots of snow….
thanks
Carolyn says
Do you mean for the chocolate ganache? I’d think that would work well enough…
Sally says
Yes for the chocolate ganache. Do I use the oil and the butter both?
Carolyn says
Yes, I think you would have to. Unsweetened chocolate has cocoa butter in it, which is what you are replacing when you put oil in with the unsweetened cocoa powder. Then you’d need to add the butter in for my recipe. If you find the end product too thin, I’d add a little more cocoa powder to help get the right consistency.
Sally says
Thank you. Have tried your low carb cinnamon roll coffee cake – people have asked me for the recipe and can’t believe that it is made with almond flour. Have made your cupcakes, hazelnut cake, chocolate cake, crab cakes and others. The pancakes are the best – my husband can eat pancakes again. He can’t have sugar or wheat products. Keep the great recipes coming. Have modified a cookie recipe for him as well.
Carolyn says
Thanks, Sally!
Jenny Jiang says
This looks amazing!
Is Swerve a must? Can I just use erythritol?
Carolyn says
You can certainly try regular erythritol but I cannot guarantee the results.
RavieNomNoms says
I saw this on Facebook a few days back and it blew my mind!! Looks so awesome!
Morgan says
Is there a substitute for the almond flour?
Carolyn says
Are you allergic to almonds?
Alex says
Carolyn, you are the BEST low carb recipe wizard on the internet, hands down!
I have a son with an allergy to almonds. I usually sub out sunflower flour, but do you have a better substitution? Thank you, I am thinking I’m going to invent a new holiday just for this cake! 🙂
Carolyn says
No, I don’t really have a better substitution but you could follow my recipe for chocolate coconut flour cupcakes for the cake part itself. You’d have to triple it, probably.
Kym says
I made this cake today for my son, he turned 27 and is on a low carb diet. There are others in the family that are gluten free, this cake was amazing!! My cake was not as pretty as yours was, and I did not have to refrigerate after frosting but the taste was wonderful. I have one son who is gluten free and low carb who does not like chocolate but loved this cake. Thank You!! We all enjoyed it!!
Carolyn says
So good to hear, thanks for the feedback!
Liz says
Oh, my! I am sitting here celebrating reaching my goal of losing 30 pounds thanks to eating low carb (using MANY of your recipes, by the way). I wanted to make myself a cake, and looking at your pictures is almost good enough! I am enjoying a celebratory glass of red wine as I scroll, and I was actually praying the whole time, hoping the recipe would not involve artificial sweeteners. I simply cannot stand the chemical-aftertaste-gag-bug spray-what am I eating-thing that goes on with fake sugar. However, I WANT CAKE! If truth be told, I have tried everything but Swerve. If you can pinkie swear that I will not have the above mentioned reaction, I will make this cake. (Tomorrow. I lied….I’ve had 2 celebratory glasses and can’t get to the store right now).
Carolyn says
I’m sorry about my delayed reply, this comment got buried somehow and I only just found it. I can’t, of course, pinky swear that you will not have an aftertaste with Swerve, because every palate is different. I do not, and many others do not, but I can’t guarantee for you.
Please keep in mind that Swerve is NOT artificial sweetener. I agree with you on the artificial ones, I cannot stand the taste of sucralose or aspartame.
Kelly Aronica says
We made this last night and it was astoundingly good. You are a wizard. The peanut butter frosting is to die for. Thanks for posting your recipes!
Carolyn says
So glad you liked it!
Sherry RH says
When you say unsweetened cocoa you me a hard chocolate and not cocoa powder, correct? I am making a list for the store and want to make sure I have everything. I think this could be a new birthday cake for me!
Sherry RH says
Totally disregard my previous question. If I would have read the recipe first, I would have seen the answers to my questions. LOL
Carolyn says
As long as you’re sure you’re all set! Don’t want you to come home without the things you need… 🙂
Cathy Lee says
This looks amazing Carolyn! I was just wondering does the Swerve powdered sugar mix into the icing well without leaving a grainy feel? I was trying to make some Chocolate Buttercream Frosting with Kerrygold butter and I turned Steviva brand (which is a erythritol and Stevia blend) into powder in my Vitamix, but it was so grainy that it was practically inedible. Any advice? Thanks!
Carolyn says
I know people like to try to powder their own sweetener but there’s simply no way to get it as fine as commercial brands can do. If you buy powdered Swerve or even ZSweet, you won’t get any grittiness like that.
Melanie E. says
ZSweet just comes in one form, right? I was checking out their website and just saw granulated. You think it would dissolve enough in the frosting/ganache to not be gritty?
Carolyn says
No, Zsweet has a powdered version. You should get some of that for the frosting and ganache.
Melanie E. says
That seems to be out of stock everywhere, too! Oh dear. haha
Morgan says
Is there a substitute for the swerve sweetener? Stores in my area do not carry that brand 🙁
Thanks!
Carolyn says
What do they carry? If you can’t get powdered erythritol, I am not really sure how you can make the glaze. You might be able to make the frosting with liquid stevia or liquid sucralose.
KAthy says
You can ground your sweetner in a coffee grinder if you have one to make it powered.
Pekah says
My batter is so dry and crumbly. Is this correct?
Carolyn says
No, it shouldn’t be dry and crumbly at all. Can you add some more liquid? What brand of coconut flour did you use?
Pekah says
I added an extra cup of almond milk and 1 cup of sour cream. Still it was very dry. I used Bob’s
Red Mill coconut flour.
Carolyn says
That’s very strange. It should not have been so dry and this recipe, although I tweaked the baking soda vs. baking powder a bit, is something I’ve used many time. Did it come out of the oven yet? I use Bob’s too.
What kind of almond flour did you use?
Pekah says
Just took them out. They look dry and did not flow into a flat surface on top. Not cool enough to remove from pan yet. Fingers crossed. (not sure of the almond flour brand)
Carolyn says
I am sorry about that but I am going to guess that it’s your almond flour and that it is too coarsely ground. It may be more almond meal than almond flour. The other possibility is that you mismeasured something. Low carb, gluten-free cake batter is often thicker than ones made with regular flour but it should be a batter still, not a hard crumbly dough. I know this cake recipe works because I’ve used it numerous times. I can’t pinpoint what’s off in your case because I am not in your kitchen! I hope it worked out alright in the end.
Trina says
I had the same problem. The batter seemed thick. I split it between three 6″ pans – it looked great but the cake portion was a bit dry – not as moist as I am used to. Will definitely try again, wonder if maybe adding an extra egg or coating with a simple syrup made from the swerve mayoisten it up. Thoughts?
Carolyn says
What kind of almond flour are you using? If your batter is thick, you simply need to add a bit more liquid to the batter.
Hope says
Having some good friends over for a long overdue dinner party soon. Have finally found the perfect dessert! You’re the bomb.com Carolyn! -don’t tell my kids I wrote bomb.com! 😉
Kelly says
This looks great! Why is it that you recommend against natural peanut butter for this?
Thanks!
Carolyn says
If you want a truly smooth, creamy frosting, most natural peanut butters aren’t going to work very well.
mel_t says
this cake looks amazing! I’m not at all fond of coconut though – does it add much of a coconut taste? and can you suggest a low carb substitute if there is one?
Carolyn says
No, it does not taste like coconut at all.
Nikki says
This looks awesome! Are there substitutes for whey powder? What purpose does the whey powder serve in this? It only needs to be low-carb (we are not dairy free or anything). Thank you for the awesome recipes!
Carolyn says
Gluten is a protein that helps baked goods rise and hold their shape. In its absence, added protein like whey or hemp help do the same.
kimberly says
im in love.. my birthday is next month and what are my 2 favorite things .. dark chocolate and peanut butter omg !!!
saved me from going off my diet with this masterpiece!!!
Michele Stans says
Hi! This looks TOTALLY dee-lish! And I think I can make it dairy free pretty easily. The only thing is – that Swerve sweetener really upsets my tummy. Do you have any other suggestions? Would Stevia work and if so do you know the conversion? Thanks! M.
Carolyn says
Swerve measures cup for cup like sugar so add in as much stevia as you would sugar in this recipe. I think your ganache will be pretty bitter, though.
Tammy says
I made this yesterday while I was snowed in. Very tasty!
Carolyn says
Great way to spend a snow day!
Michelle says
This may possibly change my life. wow. I am thinking valentine’s day dinner dessert!!
🙂
Beverly says
What a success story you have made this recipe to be! In the past I have made the original recipe from Smitten Kitchen, and it is a fabulous cake. All your effort to adapt that recipe to be HEALTHY as well as delicious and beautiful and tasty is SOOO appreciated. Thank you very much, Carolyn.
To other bakers RE: Coconut flour. All recipes use so little that it is good to always have it on hand. One pound will last a very long time. Nuts.com and Tropical Traditions are good sources.
Carolyn says
Thanks, Beverly. And you’re right on coconut flour…it lasts a long time and when used in small quantities like this, you don’t get any flavour from it.
TL says
So far, my favorite gluten-free recipes have been a combination of almond & coconut flour; it seems to solve the texture issue. And don’t think you won’t like it if you don’t like coconut; it will not last like coconut at all!
Thanks for this recipe; it looks amazing! Would it be possible to substitute monk fruit sweetner for the Swerve? That’s all I have on hand. I know that I wouldn’t need to use as much, so I didn’t know how it might affect the texture.
Carolyn says
You should be able to, but it may affect the frosting a little – you may need to add less liquid. Not sure how the ganache will fare, it may end up a little thinner.