Nick Malgieri cooked up this variation on his much-loved Supernatural Brownies, the recipe for which first appeared in "Chocolate" (HarperCollins, $40). If you find yourself with extra Butterfingers, you could substitute 30 mini bars for the 20 Peanut Butter Cups called for here.
Peanut Butter Cup Brownies
1 cup (2 sticks) unsalted butter, cut up, plus 2 tablespoon to butter pan
8 ounces bittersweet or semisweet chocolate, cut into 1/4-inch pieces
4 large eggs
1/2 teaspoon salt
1 cup granulated sugar
1 cup packed dark brown sugar
2 teaspoons vanilla
1 cup flour
20 Reese's Peanut Butter Cups (full size)
1/2 to 1 cup roasted peanuts, chopped
1. Butter a 9-by-13-by-2-inch pan, then line with foil and butter foil. Set aside.
2. Bring saucepan of water to boil and turn off heat. Combine butter and chocolate in heatproof bowl and set over the pan of hot water, stirring occasionally until melted.
3. Whisk eggs in large bowl. Whisk in salt, sugars and vanilla. Stir in chocolate and butter mixture, then fold in flour.
4. Pour 1/2 of batter into prepared pan and spread evenly. Place peanut butter cups on top of batter, spacing evenly. Pour remaining batter over peanut butter cups and spread evenly. Decorate top with chopped peanuts.
5. Bake on middle rack at 350 degrees about 45 minutes or until top has formed a shiny crust and batter is moderately firm. Cool in pan on wire rack for at least 2 hours or in refrigerator for 1 hour to allow peanut butter cups to firm up again before cutting. Wrap pan in plastic wrap and keep at room temperature or refrigerate until next day to make brownies easier to cut. Or you can wrap pan in plastic wrap and freeze for several weeks.
6. To cut brownies, unmold onto cutting board, remove foil and place another cutting board on top. Turn cake right side up and trim away edges. Cut into 2-inch squares. Wrap individually in plastic wrap and place in layers between parchment or wax paper in tin or plastic container that has a tight-fitting cover. Store at room temperature or freeze. Makes 24 (2-inch) pieces.