Prep the pan and oven: Heat oven to 375°F (190°C). Line a 12-cup muffin tin with paper liners or lightly grease each cup.
Prep the mango: Peel and finely chop ripe mango, or pulse it into a chunky puree. You want about 1 cup.
If it’s very juicy, lightly blot with a paper towel so the batter doesn’t get watery.
Mix dry ingredients: In a large bowl, whisk flour, baking powder, baking soda, salt, and cinnamon if using.
Mix wet ingredients: In another bowl, whisk sugar, yogurt, oil, eggs, and vanilla until smooth. Stir in the mango and any zest.
Combine gently: Pour wet into dry. Stir with a spatula just until the flour disappears.
It’s okay if the batter looks a little lumpy. Overmixing makes tough muffins.
Fill the cups: Divide the batter evenly among the 12 muffin cups, about 3/4 full. Sprinkle a pinch of sugar or coconut on top if you like a light crust.
Bake: Bake 15–18 minutes, until the tops are set and a toothpick comes out with a few moist crumbs.
If using mini muffins, start checking at 10 minutes.
Cool: Let muffins rest in the pan 5 minutes, then move to a rack to cool. They’ll finish setting as they cool, staying soft inside.