Have you ever tried peanut butter cookies? This moist vanilla cake is filled and decorated with lots of Nutter Butter cookie pieces and a smooth peanut butter Buttercream!
The perfect peanut butter lover's cake! Sweet and salty Nutter Butter cookies, soft vanilla cake and the most indulgent Peanut butter buttercream.
Trouble shooting and learning process
When I made this cake I encountered some struggles. I learned it the hard way that adding cookie pieces into the cake layers was not the brightest idea. When I tried cutting the cake it was quite difficult to cut through the cookies. If I make this cake again I would probably make a nutter butter cookie crust underneath the cake instead. Check the Pro tips section at the end of this recipe for instructions.
Another tip is I made way to much butter cream for this cake since I did not consider the amount of peanut butter, which adds a lot of volume. Normally a 3 layer 8 inch cake needs about 8 to 10 cups buttercream depending on the decoration and how much is used for the filling. To make this amount of buttercream I usually use double my standard Swiss meringue buttercream recipe and add the flavoring. However, For this peanut butter buttercream the flavoring (peanut butter) adds a lot of volume if you like a strong peanut butter taste. So I ended up with almost half of the frosting left over. Do not worry, I adjusted the amount of ingredients in the recipe. Just in case if you are wondering why I only made a small batch of buttercream.
Nutter Butter Peanut Butter Cake
Ingredients for 3 8-inch cake layers Vanilla cake:
1 3/4 cups (350 g) sugar
4 1/4 cups (510 g) cake flour
2 tsp baking powder
1 1/2 tsp baking soda
1 tsp salt
1 1/2 cups (360 ml) butter milk
1/3 cup (80g) unsalted butter, softened
3/4 cup (175 ml) vegetable oil
3 teaspoons vanilla
15 crushed Nutter Butter cookies
Peanut Butter Buttercream:
6 egg whites
1 1/2 cups (300 g) sugar
1 1/2 cups (340 g) butter
2 tsp vanilla
2 1/2 cups (600 g) peanut butter, smooth and at room temperature
For the drip:
1/4 cup (75 ml) heavy cream
3 oz (100 g) dark chocolate
Preheat the oven to 350 °F. Start off with a medium sized bowl. Sift in flour, baking soda and baking powder. In a large mixing bowl combine the sugar, butter, salt, and oil. Mix for about 4 minutes. The mixture should be very fluffy and lighter in color. Add eggs, vanilla and butter milk. Mix it until fluffy. Sift in the flour mixture. Mix the batter until everything is thoroughly incorporated. But do not over mix it!
Grease and line the baking pans with parchment paper. Divide the batter evenly among 3 8-inch cake pans. Add the Nutter Butter cookie pieces and mix them in. I recommend to add small pieces of cookies since the big pieces might make it harder to cut the final cake. Bake for 25 minutes at 350 °F, or until a toothpick inserted in the center of each layer comes out clean. Cool the layers in the pans for 10 minutes before transferring to a wire rack to cool completely.
For the Swiss meringue buttercream whisk egg whites and sugar in a fat-free heatproof bowl and place it on a pot with simmering water (bain-marie). Whisk it continually for about 7 minutes. The mixture is warm enough when the sugar has fully dissolved.
Take the meringue out of the water bath and whisk it with a stand mixer or hand mixer until stiff peaks form. I like to fill it into a bigger mixing bowl at this step. When the meringue is stiff, mix in the butter in small pieces. Keep mixing it until it comes together in a smooth buttercream. Add the vanilla and peanut butter and mix it in. I like to add a lot of peanut butter for flavor and color.
To decorate the cake place the bottom layer on a plate and spread a thin layer of buttercream on top and smooth it out. Add the second cake layer and repeat the step . Cover the cake with buttercream on the top and its sides. Smooth it out and let it cool in the fridge for about 40 minutes or place it in the freezer for 8 to 10 minutes. When the cake is cooled add a final layer of buttercream and smooth it.
Let the cake cool for at least 40 minutes while making the chocolate ganache. Bring the heavy cream to a simmer or heat it for about 40 seconds in the microwave. Pour the hot cream over the chopped chocolate in a heat proof bowl. Let it sit for 3 minutes, then whisk it until it comes together. It should have a smooth consistency but not be too runny. Let the ganache cool to almost room temperature while the cake is cooling in the fridge. I like to fill the ganache in a piping bottle but you can also use a small spoon to add the drip or pour everything on top of the cake and smooth it with a offset spatula to make it drip from the sides. Place it in the fridge for 5 minutes to let the drip set.
While the cake is in the fridge add some powdered sugar to about 2 cups of Swiss meringue buttercream to make it stiffer for easier piping. Decorate the cake with small dollops and nutter butter cookies. The cake might not be as easy to cut since the nutter butter cookie pieces stay pretty hard. If it should be the case I found it easier to cut in a sawing motion. Be careful to not press to much since the cake might fall apart.
Make a nutter butter cookie crust: Simply crush 25 cookies with a food processor and add 5 tbsp of melted butter. Mix it and divide it between the greased and lined cake pans. Press it down with a spatula or a cup. Bake it for about 10 minutes at 350 °F. While it is cooling make the cake batter. When the cookie crust is cooled fill in the cake batter and bake accordingly to the recipe.
You can use any type of peanut butter cookies to decorate or add to the cake batter. I believe Girl Scouts cookies would be lovely, too!
You want to bake a smaller cake? For 6 inch I recommend using half of the cake batter for 3 layers.
Not a peanut butter fan? Make it an almond butter or cashew butter cake! Just make sure not to use organic nut butter since it might split in the buttercream. Also you can substitute 1/2 cup of flour with the same amount of almond meal. It enhances the flavor and structure of the cake.