Preheat the oven to 350°F (180°C). Line the bottoms of 3 9-inch round cake pans with parchment paper and grease with nonstick spray.
Make the cake: Grate the carrots on the large holes of a box grater. You should have about 6 cups.
In a large bowl, combine the grated carrots and buttermilk and stir until the carrots are completely coated.
In a medium bowl, sift together the all-purpose and whole wheat flours, baking powder, cinnamon, ginger, salt, baking soda, cloves, allspice and nutmeg.
In the bowl of a stand mixer fitted with the whisk attachment (or in a large bowl with an electric hand mixer), combine the brown and granulated sugars, eggs, and vanilla. Beat on medium speed until the mixture drips from the whisk in ribbons, about 3 minutes.
With the mixer running on medium speed, slowly drizzle in the vegetable oil, scraping down the sides of the bowl halfway through, if necessary. Continue mixing until the mixture is fully emulsified, about 2 minutes.
Add ⅓ of the flour mixture and mix on low speed until just combined. Add ½ of the carrot mixture and continue mixing on low speed until incorporated. Continue alternating adding the flour and carrot mixture. Remove the bowl from the mixer and use a flat rubber spatula to bring the batter together.
Evenly divide the batter between the prepared cake pans.
Bake until a toothpick inserted into the center of a cake comes out clean, about 25 minutes. Let the cakes cool for about 10 minutes, then remove from the pans and let cool completely.
Make the frosting: In the bowl of a stand mixer fitted with the paddle attachment (or in a large bowl with an electric hand mixer), cream together the butter, cream cheese, vanilla extract, salt, and vanilla bean seeds until creamy, about 1 minute. Add the powdered sugar and continue mixing until silky and smooth, about 4 minutes.
Assemble the cake: Dab a bit of frosting on a cake board and place a cake layer on top. Scoop 1 cup of frosting onto the cake. Repeat with the remaining 2 layers. Use the remaining frosting to coat the top of the cake completely, leaving the sides naked.
Slice and serve.
Enjoy!
Nutritional Facts
Per 12 servings
Calories: 744
Carbohydrate: 107g
Fat: 32g
Fiber: 14g
Protein: 10g
Sugar: 75g
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