Chocolate Peanut Butter (Buckeye) Brownies

0 Preheat oven to 350 F. Line a 9×13 pan with parchment paper (leave ends hanging over the edges so you can lift the brownies out after baking.)
1 For the brownies, melt the butter in a large saucepan. Remove from heat and whisk in sugar. Beat in eggs and vanilla until smooth. Add cocoa, baking powder and salt and stir to combine. Add flour and stir until smooth. Spread into pan and bake until cooked through, 25-30 min. Cool completely before frosting.
2 For peanut butter layer, beat all ingredients until light and fluffy. Add milk a bit at a time, if needed, to reach a smooth, spreadable consistency. Once the brownies are cool, spread the peanut butter layer over the top and refrigerate until set, about 30 minutes.
3 For the ganache layer, combine all ingredients in a microwave safe bowl. Melt slowly in 20 second increments in the microwave, stirring well each time. When smooth, pour over the top of the brownies and spread with a spatula until even. Return to the refrigerator to set. Slice and serve!