Banana Nutella Muffins

Preheat the oven to 350 degrees F. Prepare a 12-cup muffin tin with liners or baking spray. In a medium size bowl, mash the bananas, add the melted butter, and mix together. Add the eggs and Greek yogurt, mix again to incorporate. Next, add the vanilla extract, brown sugar, and cinnamon. Stir gently to incorporate. In a large bowl, whisk together the flour, baking soda, sugar, and salt. Then add the mashed banana mixture to the dry ingredients. Fold together until well incorporated. Divide batter evenly among prepared muffin tin, about 3/4 of the way full. Then add Nutella to a microwave safe bowl, melt in the microwave for about 20 seconds. Drizzle the Nutella over the muffins, using a butter knife or toothpick, swirl the Nutella into each cupcake. Bake for about 20 minutes or until a toothpick comes out clean. Allow muffins to cool before serving.