M&M’s Peanut Butter Cake with Peanut Butter Frosting
Rich, moist peanut butter cake studded with colorful M&M’s and topped with creamy peanut butter frosting—an easy, nostalgic treat perfect for celebrations and sweet cravings.
Equipment
- 9x13 inch baking pan
- Mixing bowl
- hand mixer or stand mixer
- Spatula
- Wire rack
Ingredients
For the Cake
- 1.5 cups all-purpose flour
- 1 cup granulated sugar
- 0.5 cup packed brown sugar
- 0.5 cup creamy peanut butter
- 0.5 cup unsalted butter, softened
- 3 large eggs
- 1 tsp vanilla extract
- 1 cup milk
- 1 tsp baking powder
- 0.5 tsp baking soda
- 0.5 tsp salt
- 1 cup M&M’s reserve some for decorating on top
For the Peanut Butter Frosting
- 0.5 cup creamy peanut butter
- 0.5 cup unsalted butter
- 2 cups powdered sugar
- 2 tbsp milk or as needed for consistency
Instructions
- Step 1: Preheat oven to 350°F (175°C). Grease a 9×13 inch baking pan with butter or non-stick spray.
- Step 2: In a large mixing bowl, cream together the butter, peanut butter, granulated sugar, and brown sugar until light and fluffy using a hand or stand mixer.
- Step 3: Add the eggs one at a time, mixing well after each addition. Stir in the vanilla extract.
- Step 4: In a separate bowl, whisk together the flour, baking powder, baking soda, and salt.
- Step 5: Gradually add the dry ingredients to the wet mixture, alternating with the milk. Begin and end with the dry ingredients, mixing just until smooth.
- Step 6: Gently fold in the M&M’s with a spatula, being careful not to break them.
- Step 7: Pour batter into prepared pan and smooth the surface.
- Step 8: Bake for 25–30 minutes or until a toothpick inserted in the center comes out clean. Check doneness at 25 minutes.
- Step 9: Allow cake to cool completely in the pan on a wire rack.
- Step 10: Spread peanut butter frosting evenly over the cooled cake and decorate with reserved M&M’s.
Notes
For a gluten-free option, substitute all-purpose flour with a 1:1 gluten-free blend. Use almond, oat, or coconut milk as dairy-free alternatives. Add chopped peanuts or peanut butter chips for extra texture. Try Reese’s Pieces or mini peanut butter cups instead of M&M’s. Swirl melted chocolate or sprinkle sea salt on top for added flavor.