½ cup of topping for rolling (cocoa powder, coconut flakes, powdered sugar or finely chopped nuts)
In a small bowl, add the chocolate chips. Melt them in the microwave at 50% power, or in a double boiler. Melt slowly and stir often. When they have melted entirely, stir in the mashed potatoes.
Add the vanilla.
Stir, stir, stir. And stir until you cannot stir any more.
Place the mixture in the fridge to firm up for 30 minutes.
Pour your rolling mixture(s) in little bowls and have them ready. Take 1 tablespoon-sized hunks and roll between the palms of your hands. Roll in desired topping, then place on a baking sheet and refrigerate until firm.