Line a 12-cup muffin tin. Preheat to 425°F (220°C). Whisk flour, baking powder, baking soda, salt, and spice. Whisk sugars, eggs, and oil until slightly thick and glossy (30–45 sec). Whisk in mango purée, buttermilk (or coconut milk), vanilla, and citrus zest. Pour dry into wet. Fold gently with a spatula until a few flour streaks remain—don’t overmix

Toss diced mango with 1 tsp flour, then fold into batter just to distribute. Batter will be thick and spoonable. Divide batter evenly to the top of each cup (a heaping ¼ cup per muffin). Sprinkle with turbinado sugar or coconut topping if using.

Bake high, then low: Bake 5 minutes at 425°F, then without opening the oven reduce to 350°F (175°C) and bake 13–17 minutes more, until tops are domed and spring back or a tester comes out with moist crumbs. Rest in pan 5 minutes, then transfer to a rack. Let cool at least 15 minutes for crumb to set.

Notes & Variations: Texture control: If your purée was very thin or fruit extremely juicy, add 1–2 tbsp extra flour to the batter. Mix-ins (½ cup total): white chocolate chips, toasted coconut, or chopped macadamias. Mini muffins: Bake 10–12 min at 350°F (no high-heat start). Jumbo muffins (6): 425°F for 5 min, then 350°F for 18–22 min longer. Storage: Airtight at room temp 1–2 days, or refrigerate up to 4 days. Freeze up to 2 months; thaw at room temp and warm 5 min at 325°F (165°C).