Prepare brownies to package directions using a 9x9 square pan lined with parchment - leaving 1" overhang on the sides
Remove baked brownies & allow to cool on wire rack in pan before adding frosting
While the brownies are cooling, prepare your frosting
Place softened butter in mixing bowl & beat until light & fluffy
Add confectioners sugar & mix until crumbly
Add milk & beat on med-high until well incorporated & fluffy
Continue beating while you add your drops of food color, doing 4-5 drops at a time until you reach desired color
Spread on cooled brownies
Remove brownies from the pan by lifting up on parchment
Cut into 16 even squares
Add jimmies & eyes
Enjoy!