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
Ingredients
Cake
- 2 cups (224 g) almond flour
- 3/4 cup (136.5 g) Swerve Sweetener, or other granular sweetener
- 6 tbsp dark cocoa powder, or Dutch process
- 1/3 cup (36 g) unflavoured whey protein powder, or egg white protein powder
- 2 1/2 tsp (2.5 tsp) baking powder
- 1/2 tsp (0.5 tsp) salt
- 1/2 cup (115 g) sour cream, softened
- 3 large eggs
- 1 tsp vanilla extract
- 2 to 4 tbsp (2 tbsp) water
Peanut Butter Frosting
- 3/4 cup (193.5 g) creamy peanut butter
- 4 ounces (113.4 g) cream cheese, softened
- 1/2 cup (113.5 g) butter, softened
- 3/4 cup (136.5 g) Swerve Confectioners, or other powdered sweetener
- 1 tsp vanilla extract
- 3/4 cup (178.5 g) heavy whipping cream
Chocolate Glaze
- 1/4 cup (59.5 g) heavy whipping cream
- 1 oz (28.35 g) unsweetened chocolate, chopped
- 1 tbsp Swerve Confectioners
- 1 tbsp 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.
Notes
Nutrition
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Made this over the weekend. Everyone LOOOVVVED it! I didn’t have any more cream cheese for the frosting as I used it all up in the cassarole for Sunday dinner. I made it with Mascarpone Cheese instead!!! How yummily awesome!
Thanks for another super dessert.
I really loved the peanut butter and chocolate ganache frosting. The cake didn’t taste as good but the frosting helped.
cashew butter instead of peanut butter? others who have tried almond butter etc please feel free to comment 🙂
Hi! This looks amazing! I want to make it for our church potluck on Sunday…I don’t have the swerve sweetener though, and I see it’s a bit pricey online. Can I sub for Coconut Sugar instead?
Also, I have some fresh pressed peanut butter on hand. Would that work okay?
Thanks!
The coconut sugar might be okay in the cake but you simply can’t use it for the frosting.
Great, thanks!
Carolyn:
I recently signed up for your site after finding many recipes on it! You are my go to site! Just made this cake for work last week and everyone, even the carbers loved it!!! Thank you so much for all your genius work!!! On to the next recipe!!!
I am so glad to hear it!
I just made this cake for my daughter’s birthday. The cake is incredibly delicious. I feel guilty eating it and do have to remind myself that it is within my diet plan. I followed the recipe with two exceptions. I used chocolate flavored whey protein powder since that’s all I had on hand and I used a different name brand sweetener for baking instead of swerve. My cakes did not rise like I thought they would. The consistency of the batter was like brownie mix. Any thoughts or suggestions? Thanks 🙂
What kind of sweetener did you use? I think some of the ones that don’t have a lot of bulk keep the cakes from rising as well.
Hi! I made this amazing cake last year for my daughter’s first birthday (actually I made three of them because my husband’s family is huge!) Anyway, my question is could you use THM baking blend in place of the almond and coconut flour? I’m going to make this cake again for her second birthday this weekend and don’t have time order the good smooth almond flour. I ground the almond flour last year, and could do the same this year but was just trying to save myself a step.
Hi Libby. It’s going to be a lot drier with baking blend so while you can sub it out, I would add more butter and maybe even an extra egg.
Thanks for the quick reply!! Since I know for sure your recipe is great, I’m going to stick with it, especially for something as important as a birthday cake!!
Hi, can you omit or substitute the protein powder???
No, it helps the cake rise and hold its shape. If you omit, it may not rise as well.
Hooooooh boy! This cake is mind blowingly delicious! The frosting is super rich and fluffy, the ganache was perfect and hardened splendidly, and the cake itself is flavorful and moist!
My wife has repeatedly said she can’t get over how good this cake is! You could serve this at a party and no one would know!!
NOTE: I used mostly xylitol, and some stevia powder, for the sweetener.
So glad you both liked it!
Being new to baking and seeing two different types of Sweve, should I be using the granulated or powdered version?
If I say powdered, it’s powdered. If I just say Swerve, it’s granulated.
Thank you kindly!
Carolyn:
I want to make this for my husband’s birthday on Friday. We cannot find the unflavored whey or any of the substitutes you mention in your comments. I have found a Peanut Butter powder: PBFit. Do you think this would work? I can only imagine it would help intensify the peanut butter flavor….
That won’t have quite the same effect, I don’t think. You can skip it, but your cake won’t rise as much. Can you find vanilla protein powder and skip the vanilla extract?
Hey we only have the erithritol/stevia/xylitol blend is it ok if I use that instead of swerve?
Yes, that should work. You may want to powder it for the frosting.
Beautiful cake! Any substitutions for the whey protein and stevia extract? We have some low carb dieters and artifical sweetener allergies in this house. Trying to bake a cake that everyone can have for a birthday treat. Thanks!
You need a dry protein to help the cake rise and hold its shape. You can use egg white protein powder instead. Stevia is not an artificial sweetener but if someone is allergic to it, you can use a little more Swerve instead.
this turned out so dry 🙁
I will be frank, if it turned out dry, you did something wrong, because I’ve made the cake part of this many times. The culprit could be a few things…the almond flour (did you use almond meal instead?), the cocoa, the sweetener, etc.
What recipe analyzer did you use?
Hi, I have a home based bakery business and I just started the keto diet, so you know I have a sweet tooth lol. Anyway, what recipe analyzer did you use? I can’t seem to find the proper one to match the macros you posted. Thank you!
I use MacGourmet, it’s a software system I had to buy for my computer and it pulls from the USDA database so it’s much more reliable than say My Fitness Pal.
Yesterday was my birthday and I knew I wanted to treat myself with a dessert that contained chocolate and peanut butter (the absolute best combination) but I’m to the point in my low carb journey that I refuse to cheat. It’s just not worth the guilt and the way I feel about myself. I knew I could count on you, Carolyn, to have exactly what I was craving. As in most low carb desserts, almond flour is required and I have always ground my own almonds because it’s much cheaper. But I like to take the time to read the comments on any new recipe I want to make. In doing so, I knew I would need to finally break down and buy the finely ground blanched almonds so I splurged and bought the 5lb Honeyville. I’m so glad I did! This cake was divine, decadent, heaven in your mouth!!!! Wow! I didn’t use dark cocoa because I didn’t have any and so just used regular cocoa. It was amazing anyway! I also didn’t make the ganache as I’m not a huge fan of ganache and figured I’d save a few calories by doing so. Thank you so much, Carolyn, for all your hard work creating such awesome desserts!!! You are my go-to when I’m craving a delicious yummy!!!
Can you tell how much almond flour to use in place of coconut flour? I have an allergy to coconut:(
Thank you
! cup of almond flour to replace the coconut flour should be about right.
I realize this us a “healthy” food blog but your chocolate topping is not ganache, as ganache, by definition (see below) is chocolate and cream. You need to either call it chocolate topping, frosting, icing, etc. or “faux ganache.” on all recipes containing this concoction. It is blogs like these that gave destroyed culinary (usually French) techniques and throw their true meanings out the window.
“Ganache (/ɡəˈnɑːʃ/; from the French word for “jowl”)[1] is a glaze, icing, sauce, or filling for pastries made from chocolate and cream.[2]”
Oh for heaven’s sake, lighten up!
Very mature. Thank you. I will definitely be sticking to following actual chefs who know what they are talking about.
Come now. You have to admit that your comments about “blogs like these destroying French culinary techniques” was designed to be inflammatory. I simply didn’t feel like rising to the bait.
Wow. Lighten up indeed.
Hi Carolyn,
Might pureed avocado replace butter or a portion of the butter required in the cake, frosting or ganche? I have considered trying it in baking desserts, but I haven’t done so yet. I know avocados have a tremenodus enromous water which may require other liquids in the recipe to be reduced. It may be more trouble that it is worth, but I hope not.
I really don’t know, as I didn’t try it in this recipe. You’re certainly welcome to do so!
Thanks so much. Although you haven’t tried to do it, does it seem plausible?
Sure. I would hold back on added liquid until you see how thick the batter is. Gluten-free batters like this are thicker than ones made with flour as it is…but it should be spreadable, still.