Prepare your workspace: Set out some wax paper. Melt the white and red chocolate melts in separate small bowls according to package instructions.
Dip the cookies: Hold a blonde Oreo cookie with a fork or dipping tool. Tilt the bowl so that the chocolate moves to one side. Dip one-third of the cookie into the white chocolate and let it set slightly. Flip the cookie over and dip the opposite side into red chocolate, leaving the center of the cookie untouched.Place the cookie onto wax paper to dry.
Add Santa’s nose: While the chocolate is still melted, place a red M&M onto the white chocolate section to create Santa’s signature nose. Press gently so it sticks.
Create the hat: Cut a mini marshmallow in half and place it on the red chocolate section to resemble the fluffy tip of Santa’s hat.
Add the eyes: Using black decorating gel, pipe two small dots onto the white chocolate portion for Santa’s eyes.
Let them set: Allow the cookies to set completely at room temperature, or place them briefly in the fridge to speed up the process.