Brush an 8-inch iron skillet with the melted butter. Arrange the pieces of bread in a circle in the skillet. In a large bowl mix the eggs, milk, 1 teaspoon of cinnamon, ¼ cup of sugar, vanilla extract and salt.
Drizzle the warmed Nutella over the top of the bread in the skillet.
Sprinkle sugar over the top of the bread. Bake in a preheated 350°F. oven for 45 to 60 minutes or until the egg mixture has set in the center of the pan.