Preheat oven to 350 degF.
Combine oatmeal, sugar, baking powder, baking soda, salt, and cinnamon in a bowl.
Stir pumpkin, vanilla extract, egg, and yogurt into the dry mix.
Fold in chocolate chips.
Fill muffins tins lined coated with cooking spray with about 1/4 of batter. (Tip: if using liners, give them a light spritz of cooking spray before filling with batter.
Bake for 20-25 minutes or until muffins are firm and lightly browned on the top.
Allow muffins to cool for 5 minutes and then remove to a wire rack to cool further.