Gather all ingredients.

Preheat the oven to 375 degrees F (190 degrees C). Grease and flour a 9x13-inch dish.

Beat together sugar and butter in a large bowl with an electric mixer until light and fluffy. Add bananas, flour, walnuts, eggs, baking soda, vanilla, and salt; mix thoroughly.

Pour batter into the prepared dish.

Bake in the preheated oven until a toothpick inserted into the center of cake comes out clean.

Cool completely, then frost as desired.