Preheat oven to 350°. Prepare Truffle Fudge Brownie Mix according to package directions using butter and eggs. Stir in melted peanut butter. Transfer to a greased 9 x 13 baking pan. Bake 20-25 minutes. Cool completely.
Cut into about 2x1¼-inch rectangles and decorate like dominos with white frosting. Makes 48 brownies.
Tip: Place on a serving platter in a dominos pattern.