Ingredients:
- 2 ½ cups (300g) all-purpose flour
- 1 teaspoon (5g) baking powder
- ½ teaspoon (2.5g) baking soda
- ½ teaspoon (3g) salt
- ¾ cup (170g) unsalted butter, softened
- 1 ½ cups (300g) granulated sugar
- ½ cup (120g) packed light brown sugar
- 1 cup (240ml) buttermilk, room temperature
- 2 large eggs, room temperature
- 2 teaspoons (10ml) vanilla extract
- 1 cup (240ml) creamy peanut butter
- ½ cup (120ml) hot water
- 1 cup (225g) unsalted butter, softened
- 4 cups (480g) powdered sugar, sifted
- 1 ½ cups (360ml) creamy peanut butter
- ¼ cup (60ml) heavy cream
- 1 teaspoon (5ml) vanilla extract
- Pinch of salt
- 4 ounces (115g) semi-sweet chocolate, finely chopped
- ½ cup (120ml) heavy cream
Instructions:
- Grease and flour two 9-inch round cake pans. Line the bottoms with parchment paper rounds.
- Whisk together flour, baking powder, baking soda, and salt in a medium bowl.
- In a large bowl, cream together the butter, granulated sugar, and brown sugar until light and fluffy.
- Beat in the eggs one at a time, then stir in the vanilla extract.
- Gradually add the dry ingredients to the wet ingredients, alternating with the buttermilk, beginning and ending with the dry ingredients.
- Beat in the peanut butter until smooth. Gradually whisk in the hot water until the batter is smooth and pourable.
- Divide the batter evenly between the prepared cake pans. Bake at 350°F (175°C) for 30-35 minutes, or until a toothpick inserted into the center comes out clean.
- Let the cakes cool in the pans for 10 minutes, then invert them onto a wire rack to cool completely.
- In a large bowl, beat the butter until light and fluffy. Gradually add the powdered sugar, beating until smooth. Beat in the peanut butter, heavy cream, vanilla extract, and salt until well combined.
- Place the chopped chocolate in a heatproof bowl. Heat the heavy cream in a saucepan until simmering. Pour the hot cream over the chocolate and let it sit for 1 minute. Whisk until smooth and glossy.
- Place one cake layer on a serving plate or cake stand. Spread with a generous layer of peanut butter buttercream. Top with the second cake layer. Frost the entire cake with the remaining buttercream.
- Drizzle the chocolate ganache over the top of the cake, allowing it to drip down the sides.
- Chill the cake for at least 30 minutes before serving.