Preheat oven to 325 degrees F. Grease three 9x5-inch loaf pans.
In a large bowl, cream butter and sugar. Add in peeled bananas and beat until smooth. Mix in eggs, sour cream, vanilla, and cinnamon until well combined. Mix in salt, baking soda, and flour. Stir in nuts, if using. Divide into prepared pans.
Bake for 45-60 minutes, or until a toothpick inserted in the center comes out clean. If the bread starts to get too brown on the top (this will occasionally happen with my oven), cover with a sheet of aluminum foil until cooked through.
Notes
Source: Adapted from http://allrecipes.com/recipe/banana-sour-cream-bread/
Recipe by Wright Family Table at https://www.wrightfamilytable.com/sour-cream-banana-bread/