Producing a delicious keto chocolate cake that is moist, airy, and perfectly sweet can be a feat, but I think I have cracked the code. The milk chocolate buttercream is the perfect balance of sweetness and rich chocolate flavor that will please all versions of chocolate lovers. I am confident that you will enjoy this keto cake with friends and family for years to come.
Keto Chocolate Cake with Milk Chocolate Buttercream
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Milk Chocolate Buttercream
- 1 cup unsalted butter, softened to room temperature
- 3 ½ cups sugar free powdered sweetener, (note 2)
- ¾ cup unsweetened cocoa powder, sifted to remove any clumps
- ½ teaspoon kosher salt
- ½ cup full fat sour cream
- 2 teaspoons vanilla extract
- 2-4 tablespoons heavy cream, room temperature, (or unsweetened almond milk)
- 2 9 inch (22cm) metal round cake pans a springform pan will also work
Make the 2 cake layers:
- Preheat the oven to 325F (150C) and spray 2 round cake pans with cooking spray. Line the bottoms of each pan with a round of parchment paper, avoiding the sides. Note: scroll past the recipe for photos to reference while making the cake.
- In a large mixing bowl, whisk together the almond flour, sweetener, baking soda, and salt. Be sure there are no remaining clumps of dry ingredients. Set aside.
- Measure out the oil in a microwave safe liquid measuring cup and microwave on high for 45 seconds. Stir in the cocoa powder until fully incorporated. Note: this helps bloom the cocoa powder for the best chocolate flavor.
- Stir the oil and cocoa mixture into the almond flour mixture. Now add in the remaining wet ingredients: sour cream, beaten eggs, and vanilla. Stir well until fully incorporated. Be sure to scrape the sides and bottom of the bowl.
- Pour the batter evenly into the two cake pans. You may want to weight each pan on a kitchen scale to be sure the same amount of batter is in each one. Bake in the center of the preheated oven for 15-18 minutes, until a toothpick comes out with a few crumbs. It's best to err on the side of caution and pull the cakes sooner than later.
- Remove the cakes from the oven to a cooling rack and cool the cakes completely before removing from the pans. Note: the center may sink a little after cooling. This is due to the use of moist ingredients to counteract the dryness of the cocoa powder. Cooking longer will alleviate this, but then you are left with a dry cake.
Make the buttercream:
- In the bowl of a stand mixer fitted with the paddle attachment, or using an electric mixer, beat the butter on medium speed until creamy, about 2 minutes.
- Add in the powdered sweetener, sifted cocoa powder, salt, sour cream, and vanilla. Beat on low speed for 30 seconds, then increase to high speed and beat for about 1 minute more. If frosting seems too thick, add in the heavy cream and beat for a 10-20 seconds longer. The heavy cream needs to be room temperature. Cold cream will affect the texture of your icing.
Assemble the layer cake:
- Remove one of the cakes from the pan and place on a cake plate with the bottom of the cake facing up. Remove the sheet of parchment paper from the bottom and discard. Cover with a ½ inch layer of frosting. Repeat with the second layer, placing it evenly on top of the frosted cake. Spread remaining frosting all over the tops and sides. I always use an offset spatula when frosting cakes.
- Cover leftover cake in an airtight container and store in the refrigerator for up to 5 days. I like using this cake carrier for storing and transporting.
- Almond flour: For the best results, look for an almond flour that is finely ground. Avoid almond meal. Also, coconut flour has not been tested in this recipe but if I were to test it, I would use ¾ cup.
- Granulated sweetener: I have linked to the one I use in the recipe card which is a monk fruit sweetener and erythritol blend. You could also use the powdered version that is needed for the frosting if you do not want to buy 2 different keto sweeteners.
- Oil: You can use melted butter or coconut oil in place of the oil, but when you refrigerate your cake, the butter or coconut oil will solidify and cause the cake to become dry. I use canola oil or olive oil for a moist cake.
- Cocoa powder: I use Hershey's cocoa powder because that's what I always have on hand. For a richer dark chocolate cake and/or frosting, use a dutch process cocoa powder.
- Sour cream: I chose sour cream for this recipe over my usual Greek Yogurt to give the cake some added richness. Greek Yogurt will also work.
- Chocolate chips: for an even richer chocolate cake, you can add sugar-free chocolate chips to the top of the cake as decoration. I would not recommend adding them to the cake batter as they may sink to the bottom.
- Other frosting options: try my cream cheese frosting or use a sweetened whipped cream for a light option.
Nutrition per serving
Nutrition is provided as a courtesy only. Please re-calculate on your own with the ingredients and amounts you used for the most accurate data.
Photos to reference while making the cake
Prepping the pans: You want to spray the cake pans really well with cooking spray. You also want to line just the bottom with rounds of parchment paper to help the cakes come out of the pans easier after baking and cooling.
Batter consistency: The cake batter should be loose and pourable, but not runny. This will give our almond flour cake the best texture and make for a moist chocolate cake.
Evenly distribute the batter: I like to use a kitchen scale and weigh the pans with the batter to make sure I have the batter evenly distributed.
Making the keto chocolate frosting: Cocoa powder is notorious for having lumps so you definitely want to sift the cocoa powder into the creamed butter for the best consistency. To make this a milk chocolate buttercream, I used Hershey's cocoa powder. For a deep chocolate flavor, you can use dutch process.
Buttercream consistency: The frosting will have a fluffy texture and be easily spreadable. If it seems too thick, you can add room temperature cream, almond milk, or coconut milk to loosen it up.
The consistency of the sugar-free sweetener in the frosting is not going to be as smooth as using powdered sugar. This is due to the nature of a sugar substitute with sugar alcohols such as erythritol. You could try allulose which is supposed to cream into the butter much more smoothly. I haven't tried it so I cannot say for sure.
Frosting the cake: I am not a cake decorator by any means, but I think doing some swirls with an offset spatula is really easy to do, especially with this fluffy frosting.