Preheat the oven to 350°F (175°C).

Grease a loaf pan lightly with oil or line it with parchment paper.

In a mixing bowl, mash the ripe bananas until smooth.

Add the vegetable oil, sugar, egg, and vanilla extract to the mashed bananas and whisk until well combined.

In a separate bowl, whisk together the all-purpose flour, baking soda, and salt.

Gently fold the dry ingredients into the wet mixture until just combined, being careful not to overmix.

Pour the batter into the prepared loaf pan and spread it evenly.

Bake at 350°F (175°C) for 50–60 minutes, or until a toothpick inserted into the center comes out clean.

Allow the bread to cool in the pan for 10 minutes, then transfer to a wire rack to cool completely.