Pre-heat oven to 350ºF. Make cake mix as directed (and cookie dough, if making from scratch).

Grease a muffin pan. Press a small amount of cookie dough into the bottom of each section.

Place an Oreo on top of the cookie dough.

Using an ice cream scoop or large spoon, scoop the cake batter and place on top. Batter should fully cover the Oreo (push batter into any cracks and crevices).

Bake for 20-25 minutes, or until a toothpick inserted at the center comes out clean.

Let cakes cool for at least 15 minutes. Use a toothpick or fork to extract them from the muffin pan. Frost the tops and coat with sprinkles (if desired).