Preheat the oven to 375˚F. Line a mini muffin pan with paper liners and set aside.
In a medium bowl, mix together the flour, sugar, baking powder, baking soda, salt and cinnamon.
In a large bowl, mix together the egg, milk and oil. Slowly mix the dry ingredients into the wet ingredients until just combined.
Divide the batter evenly into the prepared mini muffin pan. Sprinkle some cinnamon sugar on top of each muffin.
Bake in the preheated oven for 9-10 minutes, or until a toothpick inserted comes out clean.