Preheat your oven to 350°F.

Mash the bananas, then measure out 2 cups using dry measuring cups. It's important to measure since banana sizes vary.

In a mixing bowl, combine the mashed bananas, vegetable oil, eggs, and vanilla extract. Stir with a spatula until mixed.

In another bowl, combine the flour, granulated sugar, baking soda, baking powder, cinnamon, salt, and 1 1/2 cups of the nuts. Save the remaining 1/2 cup of nuts to sprinkle on top if desired.

Gradually add the dry ingredients to the wet ingredients, mixing by hand just until combined. The batter will be thick.

Spray a loaf pan (either 9x5 or 8.5x4.5) with non-stick cooking spray. Pour the batter into the pan and spread it evenly with a spatula.

Place the pan in the center of the oven and bake for 45 minutes. Check if the bread is browning too much; if so, cover it loosely with aluminum foil and bake for another 10-20 minutes. If you didn't cover it at 45 minutes, check again at 55 minutes, then cover and bake for an additional 10 minutes or until a toothpick inserted in the center comes out clean.

For an 8.5x4.5 inch pan, bake for 55-65 minutes total. For a 9x5 inch pan, bake for 45-60 minutes total. Make sure you know the size of your pan.