Preheat oven to 350F, and line 15 muffin pans with paper liners.
Add oil to a large mixing bowl.
1/3 cup neutral oil
Stir in eggs, one at a time, until well-combined.
2 large eggs
Stir in vanilla extract and buttermilk.
1 teaspoon vanilla extract, 1/2 cup buttermilk
Add grated carrots, and stir in until combined.
1 ½ cups finely grated peeled carrots
Whisk in flour, sugars, baking powder, baking soda, salt, and cinnamon.
1 ½ cups sifted all-purpose flour, 1/2 cup granulated sugar, 1/2 cup light brown sugar, 3/4 teaspoon baking soda, 1/2 teaspoon baking powder, 1/2 teaspoon salt, 1 teaspoon cinnamon
Add nuts, if using, and stir until combined.
1/2 cup chopped walnuts or pecans
Evenly divide batter between prepared muffin tins, filling each ⅔-¾ of the way full.
Bake for about 18-22 minutes, or until a toothpick inserted in the center comes out with a few moist crumbs.
Allow to cool completely before frosting with cream cheese frosting.
Notes
Oil: I like to use light olive oil in this recipe, but another neutral oil, like canola oil, also works. If you would like to use liquid coconut oil, be sure that your ingredients are at room temperature to avoid solidifying the oil.
Buttermilk: Full-fat or low-fat buttermilk will work in this recipe. If you don't have buttermilk, you can make a homemade buttermilk substitute.
Flour: It's important to properly measure the flour to avoid heavy or dry cupcakes. Weighing the flour is the most accurate method for measuring the flour. You can also sift the flour, lightly spoon it into a measuring cup, and level.
Brown sugar: Feel free to use dark brown sugar if you prefer.
Spices: You can add spices or adjust the amount of cinnamon to suit your tastes.