In a large bowl, using a handheld or stand mixer, combine red velvet cake mix, butter, egg, and milk until smooth and incorporated. and blended.
Mixture will be thick.
Line an 8x8 inch pan with parchment, spray with nonstick, and spread ⅔ of your mixture into it.
Spread a layer of white chips on top, and then spread remaining batter on top of that.
Don’t worry if it looks messy, it will cook out smooth.
Bake at 350 for 20-25 minutes or until a toothpick comes out clean. Set aside to cool.
Make your icing by beating powdered sugar, butter, cream cheese, and milk until smooth.
Spread over cooled cake bars, then top with sprinkles. Cut and serve.