Cut the brownies into triangles.
In a small bowl, color half of the vanilla frosting with red gel food coloring, adding as much as needed to achieve the desired color.
Place the white frosting in a piping bag fitted with a star tip and set it aside.
Place the red frosting in a separate piping bag fitted with a star tip and set it aside.
Using the piping bag with the white frosting, pipe a row of small stars along the bottom edge of the brownie.
Switch to the piping bag with the red frosting and pipe from the bottom to the top, swirling as you go, and leave some room at the top.
Finish the brownie by piping a single white star at the very top. Repeat this process until all Santa hats are done. Enjoy.