Preheat your oven to 350ºF (175ºC) and prepare two 8.5 x 4.5-inch loaf pans by buttering them.

In a stand mixer, cream the softened butter and granulated sugar on medium speed until light and fluffy, about 3-5 minutes.

Whisk together the all-purpose flour, baking soda, and salt in a separate bowl. Set aside.

Add the eggs one at a time to the mixer on low speed, allowing each to fully incorporate.

Add the mashed bananas, vanilla extract, and buttermilk, mixing until just combined.

Gradually mix the dry ingredients into the wet mixture, stirring just until combined.

Divide the batter evenly between the prepared pans and bake for about 60 minutes, until a toothpick comes out clean.

Let the loaves cool in the pans for about 10 minutes before transferring them to a cooling rack to cool completely.