Preheat your oven to 350 degrees F (177 degrees C). Grease three 8-inch round baking pans, and for an extra layer of protection, consider lining them with parchment paper to prevent sticking.
In a medium-sized bowl, whisk together 2 1/2 cups of all-purpose flour, 2 teaspoons baking soda, 2 teaspoons ground cinnamon, 1 teaspoon freshly grated nutmeg, 1 teaspoon kosher salt, and 1/2 teaspoon ground ginger. This blend of dry ingredients will create the perfect flavor foundation for your cake.
In the bowl of a stand-up mixer, combine 1/2 cup unsalted butter (at room temperature), 1/2 cup neutral oil, 1 cup granulated sugar, and 1 cup brown sugar. Beat the mixture until it’s light and fluffy, which should take about 2 to 3 minutes. Add 4 large eggs, one at a time, mixing well after each addition.
Gradually add the dry mixture to the wet ingredients, alternating with 2/3 cup buttermilk. Mix until just combined, being careful not to overmix. Lastly, fold in 2 1/2 cups of grated carrots and 1 1/2 cups of roughly chopped walnuts.
Divide the batter evenly among the three prepared cake pans. If you want each layer to be equal, consider weighing each layer to approximately 569 grams.
Place the filled pans in the oven and bake for 30 to 45 minutes. To check for doneness, insert a skewer into the center of the cake; it should come out clean.
Once baked, allow the cakes to cool in the pans for about 5 to 10 minutes before transferring them to a cooling rack. Let them cool completely before frosting.
For the frosting, melt 3/4 cup unsalted butter in a small saucepan over medium heat. Cook until it starts to foam and bubble, then continue until you see lightly browned specks forming and a nutty aroma fills the air. Remove from heat and pour into a freezer-safe bowl to cool.
After about 10 minutes in the freezer, add 8 ounces of cream cheese (at room temperature) to the cooled butter. Beat until smooth, then gradually add 3 3/4 cups of powdered sugar, 1 teaspoon vanilla extract, 1/2 teaspoon kosher salt, and 1 1/2 tablespoons heavy cream. Beat for about 3 minutes until fluffy. If the frosting is too loose, chill it for an additional 10 minutes.
Once the cake layers are completely cool, place the first layer on a cake stand. Spread about 1/3 cup of frosting evenly on top. Add the second layer and repeat the frosting process. Place the final layer on top, covering the entire cake with the remaining frosting.
For decoration, pipe small carrots and stems on top of the cake using a piping bag fitted with a round tip. You can use food coloring for a pop of color if desired. Slice and serve your delicious Best Carrot Cake!
