2 1/2 c. unbleached all-purpose flour
1 1/4 tsp baking powder
1 tsp baking soda
1 1/4 tsp ground cinnamon
1/2 tsp ground nutmeg
1/8 tsp ground cloves
1/2 tsp table salt
1 lb. medium carrots (6 to 7 carrots), peeled
1 1/2 c. granulated sugar
1/2 c. packed light brown sugar
4 large eggs
1 1/2 c. vegetable oil , safflower oil, or canola oil
8 oz cream cheese, softened but still cool
5 Tbsp unsalted butter softened, but still cool
1 Tbsp sour cream
1/2 tsp vanilla extract
1 1/4 c. confectioners' sugar
Adjust oven rack to middle position; heat oven to 350 degrees. Grease and flour a 13 by 9-inch baking pan. Whisk together flour, baking powder, baking soda, cinnamon, nutmeg, cloves, and salt in large bowl; set aside.
In a food processor fitted with large shredding disk (I used a fine shredding disk), shred carrots (you should have about 3 cups); transfer carrots to bowl and set aside.
In bowl of standing mixer fitted with paddle attachment (or in large bowl and using hand-held mixer), beat granulated and brown sugars and eggs on medium-high until thoroughly combined, about 45 seconds. Reduce speed to medium; with mixer running, add oil in slow, steady stream, being careful to pour oil against inside of bowl (if oil begins to splatter, reduce speed to low until oil is incorporated, then resume adding oil). Increase speed to high and mix until mixture is light in color and well emulsified, about 45 seconds to 1 minute longer.
Turn off mixer and stir in carrots and dry ingredients by hand until incorporated and no streaks of flour remain. Pour into prepared pan and bake until toothpick or skewer inserted into center of cake comes out clean, about 40 minutes, rotating pan halfway through baking time.
Cool cake to room temperature in pan on wire rack, about 2 hours. When cake is cool, mix cream cheese, butter, sour cream, and vanilla at medium high speed in clean bowl of standing mixer fitted with whisk attachment (or in large bowl using handheld mixer) until well combined, about 30 seconds, scraping down bowl with rubber spatula as needed. Add confectioners’ sugar and mix until very fluffy, about 1 minute. Frost and eat!