🎂 M&M’s Peanut Butter Cake with Peanut Butter Frosting
Servings: 10–12 slices
Prep Time: 20 minutes
Cook Time: 30–35 minutes
Total Time: ~1 hour
🧁 Ingredients
For the Cake:
1 ½ cups all-purpose flour
1 tsp baking powder
½ tsp baking soda
¼ tsp salt
½ cup unsalted butter, softened
¾ cup creamy peanut butter
1 cup brown sugar, packed
2 large eggs
1 tsp vanilla extract
1 cup buttermilk (or 1 cup milk + 1 tbsp vinegar, let sit 5 mins)
For the Peanut Butter Frosting:
½ cup unsalted butter, softened
¾ cup creamy peanut butter
2 cups powdered sugar
2–3 tbsp milk or cream (as needed for texture)
1 tsp vanilla extract
Toppings:
¾ to 1 cup M&M’s (Peanut or regular—your choice!)
Optional: drizzle of melted chocolate or chocolate chips
👨🍳 Instructions
1. Preheat and Prep
Preheat your oven to 350°F (175°C). Grease and flour a 9-inch round or square cake pan, or line with parchment paper.
2. Mix Dry Ingredients
In a medium bowl, whisk together the flour, baking powder, baking soda, and salt. Set aside.
3. Cream Butter, Peanut Butter & Sugar
In a large mixing bowl, use an electric mixer to cream together the softened butter, peanut butter, and brown sugar until smooth and fluffy (about 2–3 minutes).
4. Add Eggs & Vanilla
Beat in the eggs one at a time, followed by the vanilla extract.
5. Alternate Mixing Buttermilk & Dry Ingredients
Gradually mix in the dry ingredients, alternating with the buttermilk. Start and end with the dry ingredients. Don’t overmix—just until combined.
6. Bake
Pour the batter into your prepared cake pan and spread it evenly. Bake for 30–35 minutes or until a toothpick inserted in the center comes out clean.
Let the cake cool completely before frosting.
🥄 Make the Peanut Butter Frosting
In a large bowl, beat the butter and peanut butter until smooth and creamy.
Gradually add the powdered sugar, ½ cup at a time, mixing on low speed.
Add vanilla extract and 2 tablespoons of milk or cream. Beat until light and fluffy. Add more milk, 1 teaspoon at a time, if needed for spreadable consistency.
🎉 Decorate & Finish
Spread the peanut butter frosting evenly over the cooled cake using a spatula.
Sprinkle the M&M’s generously over the top while the frosting is still soft so they stick.
Optional: Drizzle with melted chocolate or sprinkle extra chopped peanuts for crunch!
✅ Tips & Notes:
Peanut Butter Type: Use traditional creamy peanut butter (like Jif or Skippy). Natural peanut butters can be oily or separate and may affect texture.
Buttermilk Sub: No buttermilk? Mix 1 cup milk with 1 tbsp white vinegar or lemon juice and let it sit for 5 minutes.
Storage: Store covered at room temperature for up to 2 days, or refrigerate for up to 5 days. Let it come to room temp before serving.
Make Ahead: Cake can be made a day in advance. Wrap tightly and frost the next day for freshness.
Add-ins: You can also stir mini chocolate chips or crushed M&M’s into the batter for even more texture and color inside the cake.
🍴 Serving Suggestions:
Pair with cold milk or coffee.
For birthdays, top with candles and extra M&M’s around the edge.
Serve warm with a scoop of vanilla ice cream and a drizzle of chocolate syrup for a next-level dessert!