Combine the cake mix, pumpkin puree and milk in a large bowl and mix using an electric mixer {or by hand} until all of the ingredients are combined.
Line 12 muffin cups with paper liners. Use a large cookie scoop to scoop batter into the muffin cups.
Bake for 5 minutes at 425° and then reduce the oven temperature to 350°.
Continue to bake for 10-13 minutes. The muffins should spring back to the touch and the tops will not be glossy.
After baking, allow the muffins to cool in the pan for 10 minutes, then transfer them to a wire rack to cool at room temperature.
You can store any leftovers in an airtight container in the refrigerator for up to 3 days or freeze them for up to 3 months.