It's from Reese's. You can use Reese's Pieces, if you chop them up, but the chips are easier.
GLUTEN-FREE CHOCOLATE & PEANUT BUTTER CHIP BROWNIES
3/4 cup butter, melted
1-1/2 cups sugar
1-1/2 teaspoons vanilla extract
3/4 cup gluten-free all-purpose baking mix
1/2 cup HERSHEY'S Cocoa
1-2/3 cups (10-oz. pkg.) REESE'S Peanut Butter Chips
Heat oven to 350°F.
Grease 13x9x2-inch baking pan.
Combine butter, sugar, and vanilla in large bowl. Add eggs; beat well with spoon.
Stir together baking mix and cocoa; gradually add to egg mixture, beating until well blended.
Stir in peanut butter chips.
Spread batter evenly in prepared pan.
Bake 35 to 40 minutes or until brownies begin to pull away from sides of pan.
Cool completely in pan on wire rack.
Cut into bars.
NOTE: Always read labels of each ingredient to ensure that they are gluten free prior to use.