Heat oven to 350°F. Line a 12-cup muffin pan with liners and mist lightly with spray.
Whisk flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg, and cloves in a large bowl.
In another bowl, whisk eggs, pumpkin, both sugars, buttermilk, oil, and vanilla until smooth.
Stir grated carrots into the wet mixture.
Add dry ingredients to wet and fold just until no dry streaks remain. Do not overmix.
Fold in walnuts and raisins if using.
Divide batter among cups, filling each about 3/4 full.
Bake 18–22 minutes, until tops spring back and a tester comes out clean.
Cool in pan 5 minutes, then transfer muffins to a rack to finish cooling.
Notes
Variation: Swap raisins for mini chocolate chips, or use pecans instead of walnuts. For bakery-style domes, rest the batter 10 minutes before baking. Storage: Keep at room temperature in an airtight container for 2–3 days, or freeze up to 2 months.This recipe is an original creation inspired by classic Pumpkin Carrot Muffins flavors. All ingredient ratios and instructions are independently developed.