Prepare your brownie layer: Bake a brownie recipe (homemade or box mix) in a 9×13 inch pan, then allow it to completely cool.

Make the peanut butter frosting: In the bowl of a stand mixer (or using a hand-mixer), beat together the softened butter and peanut butter until smooth and combined. On low speed, gradually beat in the powdered sugar and heavy whipping cream until the mixture is thick and fluffy. If the consistency is too stiff, add more cream a tablespoon at a time until it spreads easily.

Spread the peanut butter frosting evenly over the cooled brownie base.

Make the chocolate frosting: In a small saucepan over medium heat, add the white sugar, butter, and milk. Bring the mixture to a boil and let it boil for exactly 60 seconds. Remove from heat, then stir in the chocolate chips until completely melted and smooth.

Immediately pour the warm chocolate frosting over the peanut butter layer and use an offset spatula to gently spread it into an even layer.

Let the chocolate frosting cool for about 5 minutes – it will begin to set but should still allow you to press in the candies. While it is still slightly soft, sprinkle the chopped Reese’s Minis evenly over the top so they slightly sink in.

Allow the entire dessert to sit for around 30 minutes before cutting into squares and serving. This helps everything set and makes for cleaner slices.