In a large saucepan, melt butter over medium heat. Once melted, stir in marshmallows. Continue stirring until marshmallows are completely melted.

Turn off the heat and stir in cereal. Immediately pour out onto a greased jelly roll pan - approximately 1/4-inch thick. Let sit for 30 minutes.

Using a cookie cutter, cut circles (or any shape) out of cereal mixture. Place 1/3 cup scoop of ice cream onto one of the shapes, and top with another shape. Serve immediately.