In a mixing bowl place the dry cake mix, butter, eggs and oil. Mix until well combined.
Add green food coloring until desired color of green is reached.
Mix together the powdered sugar and cornstarch. Roll dough into balls and into powdered sugar mixture and place onto cookie sheet lined with parchment paper or silicone baking mat.
Bake 8-10 minutes until done taking care not to let cookies brown.
Remove from oven and let sit 2 minutes before placing on wire rack to cool completely.
Using green decorating gel or frosting, place a dot onto each cookie and add a red hot candy.
Recipe by Mandy's Recipe Box at https://mandysrecipeboxblog.com/the-grinch-cake-mix-cookies/