Go Back
+ servings
A slice of square chocolate cake topped with a peanut butter frosting and drizzled with melted chocolate.
Print

Chocolate Cake with Peanut Butter Frosting

This moist chocolate cake is homemade and topped with a creamy peanut butter frosting. It's absolutely delicious!
Course Dessert
Cuisine American
Prep Time 25 minutes
Cook Time 28 minutes
Total Time 53 minutes
Servings 20 servings
Calories 545kcal

Ingredients

Chocolate Cake

  • 2 1/4 cups all purpose flour
  • 1 1/2 teaspoon baking powder
  • 1/2 teaspoon baking soda
  • 1/2 teaspoon salt
  • 3/4 cup Dutch process cocoa powder see notes
  • 1 1/2 cups granulated sugar
  • 1/2 cup unsalted butter softened
  • 1/3 cup vegetable oil
  • 2 teaspoons vanilla extract
  • 1 cup milk I used 2% but any percentage will be fine
  • 1/2 cup hot water
  • 4 large eggs at room temperature

Peanut Butter Frosting

Instructions

Chocolate Cake

  • Preheat oven to 350°F. Spray a 9x13 inch pan with nonstick cooking spray that contains flour, and set aside.
  • In the bowl of a stand mixer fitted with a paddle attachment, stir the flour, baking powder, baking soda, salt, cocoa powder, and sugar. Add the butter and oil to the dry ingredients and mix on low speed until the mixture resembles sand. 
  • In a large liquid measuring cup whisk the vanilla, milk, and hot water. Pour into the dry ingredients and butter mixture and mix until combined. 
  • Add the eggs, 1 at a time, mixing after each addition. Once fully combined, pour the batter into the prepared baking pan. 
  • Bake for 28-34 minutes or until a toothpick inserted in the center comes out clean. Remove from the oven and set on a wire rack to cool completely.

Peanut Butter Frosting

  • Make the frosting: In the bowl of a stand mixer, or using a hand-held electric mixer, beat the butter and peanut butter until creamy and well combined. With the mixer on low, gradually add the powdered sugar, ½ cup at a time until all of the powdered sugar has been added. Scrape down the sides of the bowl as needed. 
  • Mix in the vanilla, salt, and milk. Turn the mixer to medium-high speed and beat for 30 seconds to 1 minute. 
  • Spread the frosting onto the cooled cake. 
  • Top the cake with mini chocolate chips or melted chocolate drizzled overtop, if desired.

Notes

The butter used in the cake needs to be very soft. If you gently poke your finger into the butter and it leaves a dent, it’s ready to use.
If using unsweetened cocoa powder, the cake will be much lighter in color and won't have as rich of a chocolate flavor. Read my Best Cocoa Powder for Baking post for more information on the differences of cocoa powders. 
Store the cake covered at room temperature for 2-3 days.
Cake recipe adapted from King Arthur Flour
 

Nutrition

Calories: 545kcal | Carbohydrates: 76g | Protein: 7g | Fat: 26g | Saturated Fat: 14g | Polyunsaturated Fat: 3g | Monounsaturated Fat: 8g | Trans Fat: 1g | Cholesterol: 75mg | Sodium: 198mg | Potassium: 215mg | Fiber: 2g | Sugar: 61g | Vitamin A: 500IU | Calcium: 50mg | Iron: 2mg