Preheat your oven to 350 degrees and grease a 9x13” baking pan with a non-stick cooking spray.
At this point, you will want to make your brownies. Follow the directions per the box or your homemade recipe.
Once your brownies are done allow them to cool and then cut them into rectangles.
Fill a decorating bag with frosting, cut a tip off the end and frost each brownie.
Place your M&M’s onto the brownies in rows of four, starting with a square of 4 blue M&M’s in the top left corner and red and white stripes for the rest of the brownies.