Preheat oven to 375 degrees F (190 degrees C). Grease 2 baking sheets with shortening.
Whisk cake mix, cinnamon together in a bowl, breaking up any lumps. Beat pumpkin, eggs, milk, and vanilla into the cake mix mixture; stir in chocolate chips until evenly distributed through the dough.
Drop rounded tablespoons of dough 2 inches apart onto prepared baking sheets.
Bake in the preheated oven until cookies begin to brown and spring back when touched. Cool 2 minutes on the baking sheet before to a wire rack to cool completely.