Preheat your oven to 350°F (175°C).

Grease the loaf pan with oil or cooking spray.

In a large mixing bowl, combine the mashed bananas, sugar, vegetable oil, eggs, and vanilla extract. Mix until smooth.

In a separate bowl, whisk together the Bisquick mix and baking soda.

Gradually add the dry mixture to the wet mixture, stirring until just combined.

Pour the batter into the prepared loaf pan, smoothing the top with a spatula.

Bake in the preheated oven for 50-55 minutes, or until a toothpick inserted in the center comes out clean.

Allow the bread to cool in the pan for about 10 minutes before transferring it to a wire rack.