Preheat oven to 350°F. Line a 9x5 loaf pan with parchment.
Whisk together flour, baking soda, baking powder, salt, and spices in a bowl.
In a separate bowl, whisk bananas, yogurt, eggs, butter, sugars, miso, and vanilla until the miso fully dissolves and the mixture is smooth.
Pour wet into dry and fold gently until just combined. Do not overwork.
Fold in nuts, chocolate, or sesame if using.
Transfer to loaf pan and smooth the top. Sprinkle sesame seeds if desired.
Bake 55 to 70 minutes or until a toothpick comes out clean. Tent with foil near the end if browning too quickly.
Cool in pan 10 to 15 minutes, then lift out and cool completely before slicing. Flavor improves after resting.