Preheat the oven to 350°F and grease a bread loaf pan with butter.
In a large mixing bowl, mix the butter and sugar together until creamed.
Add the eggs and vanilla and mix until combined.
Add the flour, baking soda, and salt into the batter and mix until just combined. Don't overmix.
Add in the greek yogurt, nuts, and bananas. Mix until combined.
Pour batter into the 9x5 bread loaf pan.
Bake for 60 minutes, or until the top is golden brown and a toothpick comes out clean when inserted into the middle of the loaf.
Allow bread to cool on a wire rack until cool.