Rub 12 muffin cups with butter or spray with cooking spray.

Microwave 1 ½ T. butter in a large microwave-safe mixing bowl for 30 seconds. Add marshmallows and heat for another minute on high to melt marshmallows. Add peanut butter and stir until smooth. Add cereal and stir to coat with marshmallow mixture.

Spoon mixture into muffin cups, dividing evenly and pressing tightly into cups with buttered fingers. Chill for about a half hour, then carefully remove from muffin cups by loosening with a knife and lifting.

Make eyes. Mash 24 mini marshmallows to make flat circles. Dab a little peanut butter on the flat end of a chocolate chip and adhere each chocolate chip to a marshmallow. Press eyes into the cereal balls, using a little peanut butter if necessary to adhere.

You can serve these little guys on a tray, or grind up more Reese’s Puffs and set them on ground cereal so they look like they’re sitting in dirt