Heat oven to 350. Spray a mini muffin pan w/ cooking spray. In bowl, whisk together flour, baking powder, salt, nutmeg, and cinnamon. In another bowl, mix together milk and pumpkin, mix well. In lg bowl, beat softened butter and 1/2 cup sugar until fluffy, mix in the egg. Gradually add dry ingredients, alternating w/ pumpkin mix into butter mix. Fill muffin tins 3/4 full. bake 20 min. Cool for 2 min. Roll each donut muffin into melted butter. Mix sugar and cinnamon in bowl. Roll muffins into cinnamon-sugar mix.