Preheat the oven to 350°F. Spray a 9x5-inch loaf pan with nonstick spray.
In a large mixing bowl, whisk together the granulated sugar and vegetable oil until combined.
1 cup granulated sugar, ½ cup vegetable oil
Add in the large eggs, mashed bananas, sour cream, and vanilla extract. Whisk together until well combined and creamy.
2 large eggs, 1 cup mashed overripe bananas, ½ cup full-fat sour cream, 1 teaspoon vanilla extract
Add in the all-purpose flour, baking soda, and salt. Stir with a wooden spoon or rubber spatula, just until the dry ingredients are moistened and fully incorporated, and no flour pockets remain in the batter. Scrape the bottom and sides of the bowl while you're mixing.
1½ cups all-purpose flour, 1 teaspoon baking soda, ½ teaspoon salt
Evenly spread the banana bread batter into the prepared loaf pan and smooth out the top.
Bake for 50-60 minutes or until the center of the bread is puffed up and domed, and a toothpick inserted comes out clean or with moist crumbs (there should be no wet batter on the toothpick).
Remove the loaf pan from the oven and let it cool in the warm pan for about 15-20 minutes. Turn out the bread onto a cooling rack and allow it cool completely, at room temperature, for about 1 hour. Slice & enjoy!