Preheat oven to 325°F. Spray a 9x5-inch loaf pan generously with nonstick spray. Set aside.
Add the bananas and butter into a large mixing bowl and whisk until combined and smooth.
3 ripe bananas, ⅓ cup unsalted butter
Add the sugar, eggs, and vanilla and mix well.
¾ cup granulated sugar, 2 large eggs, 1 teaspoon pure vanilla extract
Add the flour, baking soda, baking powder, cinnamon, and salt and mix until there are no dry spots remaining. Scrape the sides and bottom of bowl to make sure all the ingredients are incorporated.
1 teaspoon baking soda, 1 teaspoon baking powder, ½ teaspoon ground cinnamon, ¼ teaspoon kosher salt, 1½ cups bread flour
Pour batter into prepared loaf pan and smooth. Bake for 50-60 minutes or until a toothpick inserted into the center comes out clean. Keep an eye on the bread to make sure it does not get too brown. If it does, tent with a bit of aluminum foil sprayed with nonstick spray to prevent sticking.
Remove from oven and allow the bread to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely. Slice and serve.