Preheat oven to 350 degrees F. Liberally grease a 24-cavity miniature muffin pan with cooking spray. Take one dough ball and gently flatten with your hand, then place into the muffin cavity to fit. Repeat with remaining dough.

Bake the cookie cups for about 10-12 minutes or until the edges are lightly golden. Remove from the oven. Allow the cookie cups to cool for about 5 minutes, then using the handle of a wooden spoon, create small indents in the center of each cup, careful not to puncture the cup. Fill with a pinch of white chocolate chips in each cup's well.

Immediately top the cups with a single marshmallow. Allow the cups to set for another 15 minutes or so before gently removing them from the pan with a knife. Allow to cool completely on a wire rack before serving. These are best served at room temperature, or lightly warmed up before eating.