Preheat oven to 350 degrees Fahrenheit.
In a large bowl whisk together milk, egg, melted butter and vanilla.
Add flour, sugar, baking powder, salt and cinnamon and stir just until no big lumps remain.
Fill muffin pan about 2/3 full.
(If use the silicone muffin tins, you need to put them on a cookie sheet first before pouring-this is how they bake in oven since they are wobbly.)
Bake 20-24 minutes.
Remove from oven and let cool.
Combine sugar and cinnamon for topping.
Once the muffins are cool, remove from pan and dip the tops of the cupcakes in the melted butter that was set aside for the topping, and then roll the top in cinnamon sugar mixture to coat.
Ready to eat!