Melt the peanut butter chips, chocolate chips, and butter together, stirring just until fluid and smooth. You want it pourable, not hot.

Spoon some of the chocolate mixture over about 1 cup of Reese's cups at a time and stir until each piece is coated.

Sprinkle ½ cup of powdered sugar over the coated Reese's cups.

Move everything around the bowl with your hand in a circular motion until each piece separates and gets an even coating of powdered sugar.

Repeat in batches until the whole bag is coated.

Let everything sit for a few minutes so the coating firms up, then enjoy.