Preheat oven to 350℉ Line a 9 by 5 inch loaf pan with parchment or spray with non-stick spray and set aside.
In a large bowl whisk together flour, baking soda and salt. Set aside.
In bowl of electric mixer beat sugar and butter on medium until light and fluffy, about 2 minutes. Add eggs, one a time, beating well after each addition.
Add banana, yogurt, rum and vanilla to the butter mixture and beat until well blended.
Add the flour mixture, beat on low just until combed. Do not over mix. Add nuts if using. Transfer batter to prepared pan. Bake at 350℉ for 1 hour, or until tester comes out clean.
Notes
You can substitute the dark rum with 4 to 5 teaspoons of artificial rum extract.Store leftovers wrapped tightly at room temperature for up to 3 days.Freezes well. Wrap tightly and place in an airtight container or freezer bag for up to 2 months.