Alternatively you can toss donuts in powdered sugar, cinnamon or cinnamon and sugar. After donuts are baked, spray with butter or or dip in melted butter. Add some powdered sugar, cinnamon or cinnamon and sugar to a large Ziploc bag, add donuts and toss until coated. These are really good like this served warm!
For extra yumminess, before baking, spray with butter cooking spray and sprinkle with sugar!
Find it online: https://www.motherthyme.com/2019/07/3-ingredient-donuts.html