Preheat the oven to 375 degrees F (190 degrees C). Line 18 muffin cups with paper liners.

Mix spice cake mix, pumpkin purée, and cinnamon chips together in a bowl until cake mix is completely moistened; add nuts and stir. Spoon the batter into prepared muffin cups to about 2/3 full.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, 25 to 30 minutes. Cool in the pans for 10 minutes before removing to cool completely on a wire rack.