Preheat oven to 350F degrees. Line a 12 hole or two 6-hole muffin pan/s with paper cups.

In a bowl, beat egg and Nutella until well incorporated, add flour and mix until there's no more lumps. Spoon batter onto paper-lined mini muffin pan or if you don't have paper liners, just grease each muffin hole with butter or baking spray.

Bake for 8-10 minutes.  Do not over-bake. Cool in the pan for about 5 minutes then transfer to wire rack. Enjoy! :)