Preheat oven to 350°F. Line muffin pan with liners.
In a medium bowl, whisk flour, baking soda, baking powder and salt until well combined. Set aside.
In large bowl, whisk together banana, sugar, brown sugar. Beat in egg, vegetable oil and vanilla extract. Slowly whisk in the flour mixture, until there are no lumps. Fold in pecans.
Fill muffin tins 3/4 full. (You can try using this amazing little gadget to get perfectly sized muffins every time). Top each muffin with about 1 teaspoon of Nutella and use a toothpick to swirl it into the batter.
Bake muffins for 15-17 minutes, or until a toothpick inserted in the center comes out clean.
Serve warm or store in an airtight container until ready to serve.