These brownies are perfectly fudge-y and filled with peanut butter cups. And then topped with a deliciously light and fluffy peanut butter frosting that is to die for!
Preheat the oven to 350F. Line a 9x9 inch pan with either foil or parchment paper. In a large bowl, melt together the chocolate and the butter. Whisk in the sugar.
Add in the eggs, yolks, and vanilla and whisk until combined. Fold in the dry ingredients.
Spoon about 1/2 the batter into the bottom of the pan. Place the peanut butter cups in rows until the batter is covered. Top with the remaining brownie batter. Bake for 35 minutes. Allow to cool completely before frosting.
Cream together the butter and peanut butter until light. Add the powdered sugar and milk and beat until light and fluffy.
Spread the peanut butter frosting over the cool brownies and sprinkle with Reese's Pieces