Preheat the oven to 350ºF and lightly spray a donut pan with non-stick cooking spray. Use a paper towel to evenly coat the entire surface of the donut wells.

In a smaller bowl, whisk together the flour, nutmeg, sugar, baking powder, and salt until well combined. Set the dry ingredients aside.

In a separate mixing bowl, combine the milk, eggs, vanilla extract, and vegetable oil. Whisk or stir with a spatula until fully blended. Gradually add the dry flour mixture, mixing by hand with a spatula just until everything is incorporated.

Transfer the batter into a ziplock bag, then snip off one corner to pipe the batter into the donut wells. Alternatively, you can use a cookie scoop to drop dollops of batter into the wells. If the batter isn’t level, gently smooth the tops with a small spatula. Fill each well about halfway to three-quarters full.

Bake for 10-11 minutes, or until a toothpick inserted into the center of a donut comes out clean. Let the donuts cool for 10 minutes in the pan. After that, carefully flip the pan upside down and tap it on the counter a few times to release the donuts.

In a ziplock bag, combine the granulated sugar and cinnamon. Add one donut at a time to the bag and shake to coat evenly. Repeat with the remaining donuts. If the coating isn’t sticking, lightly brush the donuts with melted butter before shaking them in the cinnamon sugar bag.