Prep the pan and oven: Heat the oven to 350°F (175°C). Line a 12-cup muffin pan with paper liners or lightly grease.
Mix the wet ingredients: In a large bowl, whisk pumpkin puree, oil, brown sugar, granulated sugar, eggs, milk, and vanilla until smooth.
Add the dry ingredients: Sprinkle flour, baking powder, baking soda, salt, cinnamon, nutmeg, ginger, and cloves over the wet mixture.
Combine gently: Fold with a spatula until just combined.
A few small streaks are fine. Do not overmix.
Fold in extras: If using chocolate chips or nuts, stir them in now.
Fill the cups: Divide batter evenly among the muffin cups, about 3/4 full. Top with pepitas or coarse sugar if you like.
Bake: Place on the middle rack and bake 18–22 minutes, until the tops spring back and a toothpick comes out with a few moist crumbs.
Cool: Let muffins rest in the pan 5 minutes, then move to a wire rack to cool fully. This helps set the structure.