Brown Butter Peanut Butter Buttercream with Peanut Butter Chocolate Cake
A moist peanut butter chocolate swirl cake topped with a luscious peanut butter buttercream, baked snack cake style.
Servings 10
Ingredients
Brown Butter Peanut Butter Chocolate Swirl Cake
- 113g or ½ cup butter to be browned
- 2 large eggs at room temperature
- 200g or 1 cup fine granulated sugar
- ½ teaspoon fine sea salt
- 2 teaspoons pure vanilla extract
- 50g or ¼ cup avocado or canola oil
- 130g or ½ cup peanut butter
- 1 ½ teaspoon baking powder
- 190g or 1 ½ cup all purpose flour
- 180g or ¾ cup cup buttermilk or plain kefir
- 60g or ¼ cup water
- 2 tablespoons dutch process cocoa powder
Peanut Butter Brown Butter Buttercream
- ½ cup butter for browning
- ¼ cup butter softened
- ⅓ cup peanut butter
- 1 teaspoon pure vanilla extract
- ½ teaspoon fine sea salt
- 2 ¼ cup organic powdered sugar
- 2 tablespoons heavy cream
Instructions
To make the cake
- Preheat oven to 325 F and grease and line an 8×8 square inch pan with parchment paper.
- Over medium heat in a saucepan, melt the butter. Continue to cook while the butter sputters, bubbles and foams. Once it goes silent and turns brown, immediately remove from heat and pour into a bowl, scraping up the tiny brown bits from the pan. Let cool completely.
- In a large bowl, add the eggs and sugar. Beat with a hand mixer until light and fluffy - about 3-4 minutes. Add the salt and vanilla as you beat.
- With the beaters on, slowly pour in the oil and the cooled brown butter. Scrape up all the brown butter bits into the bowl (those are the tasty parts!). Beat to combine then add the peanut butter and beat.
- Add the flour and baking powder, and with the mixer on add the buttermilk and water. Stop beating once the batter is well mixed.
- Pour half of the batter into the prepared pan. To the other half of the batter add the cocoa and a tablespoon of water, and stir to fully combine. Then pour the now chocolate batter over the peanut butter, and use the offset spatula or a butterknife to swirl the two batters.
- Bake for 30-35 minutes, until a cake tester comes out clean of any wet crumbs.
To make the buttercream
- Brown 1/2 cup butter: Over medium heat in a saucepan, melt the butter. Continue to cook while the butter sputters, bubbles and foams. Once it goes silent and turns brown, immediately remove from heat and pour into a heatproof bowl, scraping up the tiny brown bits from the pan. Let it cool at room temperature and then set it in the fridge for a couple of hours, stirring now and then until it has solidified and is soft and creamy (like the texture of coconut oil). You can speed this up by doing it in the freezer but you’ll need to keep a closer eye on it.
- In the bowl of a stand mixer, or using a hand mixer, beat the brown butter and softened butter until light and fluffy. Add the peanut butter, vanilla and salt and beat to combine. Add the powdered sugar and beat. The mixture is going to look thick and not-spreadable, don’t worry, we are about to fix it.
- Add the heavy cream and beat until the buttercream is light and fluffy, as pictured. If it’s still not smooth, add another TB of heavy cream. Once the cake is cool, spread the buttercream over the cake.