Prep your pumpkin: For fresh puree, halve a small sugar pumpkin, scoop seeds, brush with a little oil, and roast cut-side down at 400°F (200°C) for 35–45 minutes until fork-tender. Scoop the flesh and mash or blend until smooth.
Let it cool. If it seems watery, drain in a fine-mesh strainer for 10–15 minutes.
Heat the oven: Set to 375°F (190°C). Line a 12-cup muffin tin with liners or grease lightly.
Mix dry ingredients: In a large bowl, whisk flour, baking soda, baking powder, salt, cinnamon, ginger, and nutmeg.
Mix wet ingredients: In another bowl, whisk pumpkin puree, eggs, oil, milk, sugars, and vanilla until smooth.
Combine gently: Pour wet into dry.
Stir just until no flour streaks remain. If using mix-ins, fold them in now. Do not overmix.
Fill the tin: Divide batter evenly among cups, about 3/4 full. Sprinkle coarse sugar or pumpkin seeds on top, if you like.
Bake: 18–22 minutes, until tops spring back when touched and a toothpick comes out mostly clean with a few moist crumbs.
Cool: Let muffins rest in the pan 5 minutes, then move to a rack to finish cooling.
Enjoy warm or at room temperature.