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.
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.
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
- 3 8-inch metal baking pans
- 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
- ¼ cup heavy whipping cream
- 1 oz unsweetened chocolate chopped
- 1 tablespoon Swerve Confectioners
- 1 tablespoon allulose granular
- 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.
- 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.
- 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.
I have your book but this recipe is not in the book. Glad that I checked the website. I wish you make a video of this cake. The amount of total batter was so little to spread out to the 3 pans, I wasn’t sure if I did something wrong or not. After it cooled off, I took them out and they really didn’t seem risen. I cut the cake with the round cookie cutter to save some to make the mini cake and it looks not that bad. It just didn’t rise evenly. I think that was because the batter was so small portion to spread out in the pan and quite thick even after I added some table spoons of water. I skimmed all of the comment mentioning “rise”. I suspected my baking powder, I tested it, and it is okay. I used Bob’s and one of the comment mentioned about the Bob’s and it could be the reason. I got Kirkland Almond flour and I am about to make the second batch using this flour. I have high hopes for this cake since I am a prediabetic now and one of my friend is diabetic. I am making this cake for her birthday. If it success, it will be a mega hit cause the taste of the cake is so good.
What sweetener are you using?
I have a follow up question. I also failed the second batch as well and I think that’s because I put them all on the same rack and they rise unevenly. What do I need to do? Can I bake 2 first than bake another one after 15 mins? Do I need to bake them in a different rack at the same time? What is the best way of doing it?
Hi Bora… okay, that’s interesting. Is it an older oven? Or is your floor slanted at all (as in many old houses?). You could set racks for the 3 middle positions and put them all in the center, then switch the top and bottom ones halfway through baking. Also, you had trouble with them rising the first time… are you using protein powder? What brand?
Thanks so much for response to my question.
I used swerve sweetener(slightly old), which might be a problem and Opportuniteas protein powder (www.amazon.com/gp/product/B0177EV7E4).
I am going to try the third batch either tomorrow or the day after tomorrow. The amount of batter is around 700~720g and I divided into around 220g. I tilted the pan to it can be distributed well and hit a couple of times on the countertop to remove air bubble. It might be because I didn’t evenly distributed the batter enough.
For the cake taste, I brought the mini version to church and everyone loved it and said it’s not too sweet.
If allulose isn’t used in the glaze, I assume another tablespoon of confectioners should be added? Thanks in advance!
Esther Flora says
I’ve tried adding 6 tablespoons of water and the batter is still dry and grainey. I have followed the recipe exactly. Is there a typo or missing the ingredient in the cake recipe?
No, nothing missing here. What brand of almond flour are you using?
Randy Goldman says
Can I use 2- 9” pans as apposed to 3- 8” pans.
This looks divine! I am wondering if you could make them in cupcakes?
can I use pea protein instead of whey?
Yes, that should work!