Make the Brownie Batter: Preheat oven to 350ºF and line an 8-inch square pan with parchment paper. Spray with with cooking spray.

1. Prepare brownie mix according to package instructions; set aside.

Make the Red Velvet Batter:

1. In a medium bowl, stir together all of the red velvet batter ingredients until combined. Plop about half of the red velvet batter by the spoonful into random spots in the pan. Switch to the brownie batter, plopping spoonfuls randomly over. Repeat with the remainder of the batters, then swirl with a skewer or butter knife. To create a smoother, even layer, lift entire pan a couple inches from the counter and drop. Repeat several times until even.
2. Bake in the oven for 45-50 minutes. You can’t really test for doneness with the toothpick method since the toothpick will still have some batter on it when removed. The brownies should be set on the top and only jiggle slightly. Brownies will continue baking and firm up as they cool.

Make the Frosting:

1. Place the white chocolate chips in a small microwave-safe bowl and melt in the microwave until smooth; set aside.
2. In the bowl of a stand mixer fitted with the paddle attachment, mix the butter, cream cheese and vanilla on high until creamy. Pour in the melted chocolate and continue beating until combined. Add the powdered sugar and beat on high until fluffy. Spread frosting on top of completely cooled brownies. If not serving immediately, brownies can be stored covered in the refrigerator for up to one week.