Prepare two 8" cake pans by spraying them with cooking spray. Make sure you spray them well so the cake batter doesn't stick. Preheat your oven to 350 degrees F.
In a large bowl whisk together the dry ingredients: flour, granulated sugar, brown sugar, baking soda, baking powder, salt, cinnamon and nutmeg.
Add the vegetable oil and melted butter to the dry ingredients. I used a hand mixer to mix these ingredients together. Mix until the ingredients are well combined.
Add the room temperature eggs one at a time to this mixture. Use the hand mixer to beat the eggs in, but don't over mix.
Add the vanilla extract and stir to combine.
Fold in the carrots and stir until everthing is combined. Don't over mix.
Pour your batter into your cake pans evenly. Bake for 35-40 minutes or until a toothpick inserted in the middle comes out clean.
Let your cakes cool in the pan for 5-10 minutes before taking them out to cool on a baking rack.