Defrost 3 frozen bananas and drain any excess liquid.
Preheat oven to 350 degrees F. Prepare the loaf pan. by spraying it with pan spray or lining it with parchment paper.
Measure the flour, baking soda, salt, granulated sugar, and brown sugar in a large mixing bowl. Set aside.
Using your fork and a medium bowl, mash the bananas until no large lumps remain. If using frozen bananas, drain any liquid that has formed.
In a microwave-safe dish, melt the butter until it is fully melted and liquid.
Into the bowl of mashed bananas, add melted butter, yogurt, and eggs. Mix to combine.
Fold the liquid ingredients into the dry ingredients( add optional nuts if desired) and mix until there are no more spots of dry flour.
Pour batter into a sprayed, non-stick bread pan and bake for approx.. 55 min at 350 degrees. Check for doneness by gently touching the center of the bread. It should spring back and not feel mushy below the crust.