In large saucepan melt butter over low heat. Add marshmallows and stir until completely melted. Remove from heat. Stir in vanilla.

Add cereal. Stir until well coated.

Using buttered spatula or wax paper, evenly press mixture to 1/4-inch thickness on baking sheet coated with cooking spray. Decorate with sprinkles. Refrigerate for 15 minutes.

Remove from refrigerator. Using 2-inch cookie cutters coated with cooking spray, cut into desired shapes. Place small scoop of ice cream on undecorated side of one cut-out. Top with another cut-out, decorated side up. Gently press together. Return to baking sheet. Repeat with remaining cut-outs and remaining ice cream.

Freeze for 30 minutes. Transfer to airtight container. Freeze for 2 hours to 1 week. Let stand at room temperature for 10 minutes before serving.