Preheat oven to 350F. Grease and line a 9x5 loaf pan with parchment paper 'sling' for easy removal.
In a large bowl whisk together the oil, eggs, and sour cream until lump free.
Whisk in the sugars, mashed banana, vanilla, cinnamon, baking powder and baking soda. Then fold in the flour.
Briefly heat the Nutella in a small bowl in the microwave for about 20 seconds, or until just loosened.
Add half your batter to the prepared loaf pan. Dollop half the Nutella over the batter. Gently swirl with a knife or chopstick.
Add the remaining batter to the pan. Dollop the remaining Nutella over the top. Swirl again.
Bake the bread for about 60 minutes, or until a toothpick inserted in the center comes out without wet batter on it (moist crumbs are fine.) Note: if your bread seems to be browning too quickly, lay a loose piece of foil over the top towards the end of baking. Let cool before slicing.
Nutritional information is provided as a courtesy and is an estimate only. This information comes from online calculators. Although The View from Great Island attempts to provide accurate nutritional information, these figures are only estimates.
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