Heat the oven to 375°F and line a standard 12-cup muffin pan.
Whisk the mashed banana, sugars, eggs, melted butter, yogurt, and vanilla until combined.
In another bowl, mix the flour, baking soda, baking powder, salt, and cinnamon.
Fold the dry ingredients into the wet just until no obvious dry flour remains.
Fold in chips or nuts if using. Don’t beat the batter smooth. A few lumps are entirely respectable muffin behavior.
Divide evenly among the 12 cups. They should be around ¾ full.
Bake for 18–22 minutes. Start checking around 18 minutes. They’re done when the tops spring back and a toothpick comes out with moist crumbs rather than wet batter.
Let them cool in the pan for about 5–10 minutes, then move them to a rack.