Gather ingredients (roll of cookie dough, oreo cookies, and brownie mix) and equipment (muffin tin).
Add necessary ingredients to make brownie mix.
Spray muffin tin with cooking spray.
Cut roll of cookie dough into 12 pieces (smash a layer of cookie into the bottom of each muffin cup).
Add an oreo cookie on top of the cookie dough layer.
Pour brownie batter on the top of each cup.
Sprinkle smashed oreo cookies on top of the brownie batter.
Bake at 350 for 25 minutes or until the cookie cups are cooked through.
Let cool, add a scoop of ice cream, and ENJOY.