Preheat oven to 400°F. Coat a standard-sized muffin tin with nonstick cooking spray.
Mix all ingredients together in a bowl. Whisk mixture until well combined.
Pour batter in prepared muffin tin cups, filling each cup ~3/4 of the way full. Once oven is preheated, place muffin tin in oven to bake for 15-20 minutes, or until muffin tops are golden brown.