Preheat your oven to 350°F (177°C) and adjust the rack to the lower third position. Grease a 9×5-inch loaf pan with nonstick spray or butter and set aside.
In a medium bowl, mix the dry ingredients: flour, baking soda, salt, and cinnamon. Set aside.
Using a stand mixer with a paddle or whisk, beat softened butter and sugar together for about 2 minutes until smooth and creamy. Add eggs one at a time, beating well after each. Then mix in yogurt, mashed bananas, and vanilla until fully combined.
With the mixer on low speed, gradually add the dry ingredients and mix until just combined. Be careful not to over-mix. If desired, fold in nuts.
Pour the batter into the pan and spread evenly. Bake for 60–65 minutes, loosely covering with aluminum foil halfway to prevent over-browning. The bread is done when a toothpick comes out clean with a few moist crumbs. Start checking at 60 minutes.
Remove the bread from the pan and let it cool. If not eating right away, freeze for later.