Preheat your oven to 350°F (175°C).

Cream together the softened butter and granulated sugar in a large mixing bowl until light and fluffy, about 2-3 minutes.

Add the eggs one at a time, mixing well after each addition. Fold in the mashed ripe bananas and vanilla extract.

Mix the dry ingredients by whisking together the all-purpose flour, baking soda, and salt in another bowl.

Combine the mixtures by alternating adding the dry ingredients to the wet mixture with buttermilk, starting and ending with the dry ingredients.

Pour the batter into a greased 9-inch cake pan and spread it evenly.

Bake for 30-35 minutes or until a toothpick inserted into the center comes out clean.

Cool the cake in the pan for about 10 minutes before transferring it to a wire rack to cool completely.