Description
A moist sheet cake flavored with peanut butter and topped with a creamy peanut butter frosting, baked in a pan for easy serving.
Ingredients
- ¼ cup creamy peanut butter
- 1 cup water
- ½ cup butter
- 1 cup sugar
- 1 cup brown sugar
- 2 cups flour
- 1 teaspoon salt
- 1 teaspoon baking soda
- 2 eggs
- ½ cup buttermilk (or substitute)
- 1 teaspoon vanilla
- ¾ cup butter (for frosting)
- 6 Tbsp buttermilk (for frosting)
- ½ cup peanut butter (for frosting)
- 3½ cups powdered sugar
- 1 Tbsp vanilla (for frosting)
Instructions
- Preheat oven to 375 °F (190 °C).
- In a medium saucepan, combine ¼ cup peanut butter, water, and ½ cup butter; bring to a boil, then remove from heat.
- In a mixing bowl, stir together sugar, brown sugar, flour, salt, and baking soda.
- Add the peanut butter mixture into the dry ingredients.
- Mix in eggs, buttermilk, and vanilla until well combined.
- Pour batter into a greased or parchment-lined sheet pan (about 12×17) and bake 13–15 minutes; do not overbake.
- Meanwhile, make the frosting: in a small saucepan, bring together ¾ cup butter, 6 Tbsp buttermilk, and ½ cup peanut butter to a boil.
- Remove frosting mixture from heat and stir in powdered sugar and 1 Tbsp vanilla until smooth.
- Pour the warm frosting over the warm cake, spreading evenly.
Notes
- **Buttermilk substitution**: For every cup of buttermilk called for, add 1 Tbsp lemon juice or white vinegar to a measuring cup, then fill with milk to 1 cup. Stir and let sit 5 minutes before using.
- Do not overbake the cake — it stays moist when removed at the right time.
- If using salted butter, reduce or omit added salt in the recipe.
