Mix flour, sugar, baking powder and salt in a medium bowl. In an electric mixer combine eggs, vanilla, milk and ½ cup melted butter. Then slowly add in dry ingredients until fully incorporated.
Cinnamon swirl:
Mix all the ingredients with an electric mixer until smooth
Using a donut maker:
Use the cake mixture and fill each slot ⅔ of the way full. Then top with ½ teaspoon cinnamon mixture, and closet the lid. When the light turns green, remove the donuts from the maker. After every 2-3 batches, wipe the cinnamon mixture off the lid with a paper towel to keep it clean.
Using a donut baking sheet:
Fill each spot about ⅓ of the way with the cake batter. Then put ½ teaspoon of the cinnamon mixture into each spot and then fill another ⅓ full with cake batter. Bake at 350 degrees for about 10-12 minutes (check with a toothpick)
Let the donuts cool
Frosting:
Mix ingredients until smooth. Using a spoon, drizzle the frosting over the top of the donuts.
Recipe by Our Thrifty Ideas at http://www.ourthriftyideas.com/2014/07/mini-cinnamon-roll-donuts.html