Mix cake mix, butter, egg and peppermint extract. Add in cream cheese and beat until combined.
Stir in Oreo chunks and peppermint chunks.
Refrigerate dough 30 minutes to 1 hour. Remove and roll into 1 inch ball shaped cookies.
Bake at 350 degrees for 9 minutes. Remove from oven and slightly press to flatten with back of spatula, sprinkle with crushed peppermint. Let rest on baking sheet for 2 to 3 minutes. Remove to completely cool on baking rack. Store in air tight container.