Peanut Butter Brownie Bites - unsalted butter

Method

• Preheat oven to 325°F and spray two 12-cup mini muffin pans with nonstick spray. Set aside.
• Place melted butter, sugar, cocoa powder and salt in a large bowl and stir the mixture until combined. The texture will appear granular at this point. Stir in vanilla. Then add eggs one at a time, stirring well after each one. When the batter is thick and shiny, add the flour and stir until completely incorporated, then beat briskly for 40 more strokes.
• Fill each muffin cup with a slightly rounded tablespoon of batter. Then sprinkle 1/4 teaspoon of toffee bits over each brownie. Bake for 12 to 14 minutes, until a toothpick inserted in the center comes out with a few moist crumbs attached. Then remove from the oven and cool bites completely in the pans on a wire rack. Then chill in the refrigerator 1 hour. Use an offset spatula to pop bites out of pan.
• To make the buttercream, beat butter and peanut butter in a large mixer bowl on medium speed until light and fluffy. Reduce speed to low, then gradually add powdered sugar and beat until smooth. Add vanilla and milk; beat on medium speed until airy.
• Fit a pastry bag with a round tip and put the buttercream into the bag. Pipe a spiral of buttercream onto the top of each brownie bite.
• Store leftover bites in an airtight container at room temperature up to 2 days.