Preheat oven to 350.
Line 2 baking sheets with parchment paper.
Cream together butter and powdered sugar.
Slowly add flour and continue mixing until dough forms.
Dust work surface with powdered sugar.
Roll out dough to about 1/4" thick and cut out circles
Place on prepared sheets.
Reroll as necessary to make additional circles.
Top each cookie with red and blue M&Ms.
Bake 13-14 minutes or until they are pale golden color.
Allow to cool on baking sheets.
Set out ice cream to soften slightly.
Place one scoop of ice cream on a cookie. Press another cookie gently on top to make a sandwich.
You can optionally roll the edge of the sandwich in sprinkles.
Place in freezer to set.