These bite-sized cinnamon sugar mini muffins are so sweet and delicious!
Preheat the oven to 400. Grease a mini muffin tin and set aside.
In a large bowl, whisk together the sugar, flour, baking powder, and salt. In a small bowl or measuring cup, whisk together the oil, egg, milk, and vanilla. Pour the wet ingredients into the dry ingredients and mix until just combined. Scoop the batter into the prepared muffin tin, filling 3/4 full.
Bake 12-15 minutes, or until light golden brown. Remove and let cool for 10 minutes.
After the muffins have cooled, dip the top of each muffin in melted butter, then in the cinnamon sugar. Serve warm.