Preheat the oven to 350 degrees F (175 degrees C).

Mix cake mix, oil, eggs, and peppermint extract together in a bowl.

Roll the dough into walnut-size balls and space about 2 inches apart on a cookie sheet.

Bake in the preheated oven until the tops of the cookies start to crack, about 8 minutes. Take out of the oven and let cool on the pan for about 5 minutes before moving to a cooling rack.

Beat cream cheese, butter, and vanilla extract together in a bowl with an electric mixer. Add powdered sugar a little at a time to reach desired consistency, or to sweeten to your liking.

Spread filling between 2 cooled cookies.