Makes one 9 inch double layer cake
For the batter:
¾ cup walnut halves and pieces, toasted and finely chopped
2 ¼ cups packed grated carrots (5 to 6 medium), divided
2 ¼ cups unbleached all-purpose flour
1 ½ teaspoons baking powder
1 ½ teaspoons baking soda
½ teaspoon kosher salt
2 teaspoons ground cinnamon
½ teaspoon ground ginger
½ teaspoon freshly grated nutmeg
1/8 teaspoon ground cloves
½ cup neutral oil, such as vegetable, grapeseed or sunflower
¼ cup walnut oil
1 cup plus 2 tablespoons granulated sugar divided
¾ cup brown sugar
3 large eggs
½ cup of apple sauce (preferably organic)
1 tablespoon orange zest (from 1 orange)
3 or 4 edible flowers, as garnish
For the frosting:
1 pound (2 cups) cream cheese at room temperature
¾ cups (1 ½ sticks) unsalted butter, at room temperature
1 ¾ cups confectioners’ sugar
1 teaspoon freshly squeezed lemon juice
Position a rack in the center of the oven and preheat to 325 F. Scatter the walnuts in one layer on a small rimmed baking sheet. Bake until golden brown and fragrant, shaking the pan a few times for even color. Total baking time will be between 5 and 15 minutes. Remove and set aside to cool. Lightly grease two 9-inch round cake pans with oil and line the bottoms with rounds of parchment paper. Set aside. Line a wire cooling rack and a baking sheet with parchment paper. Set aside
To make the batter, toss the chopped walnuts with 2 cups of the grated carrots in a large bowl. Set aside.
Whisk together the flour, baking powder, baking soda, salt, cinnamon, ginger, nutmeg and cloves in a medium bowl. Set aside.
In the bowl of a stand mixer fitted with the paddle attachment, mix the oils, 1 cup of granulated sugar and ¾ cup of brown sugar, eggs and apple sauce. Start on low speed and increase to medium for a total of 3 to 5 minutes, until the mixture is lighter in texture and slightly lighter in color. Scrape down the bowl with a rubber spatula to fully incorporate the ingredients. With the mixer on low speed add the flour mixture and incorporate it fairly quickly (about 20 seconds), then scrape down the bowl again. Remove the bowl from the mixer and use the rubber spatula to fold in the carrot mixer.
Divide the batter between the 2 prepared pans; they will be about two-thirds full. Using an offset spatula, smooth and level the batter for even baking. Bake for 35 to 40 minutes or until the cakes are deep golden brown and a skewer inserted into the center come out clean. Cool the cakes in the pans for 20 minutes. Run a knife along the sides of the pans and invert the cakes onto the prepared rack. Carefully remove the parchment paper and cool completely.
Meanwhile, to make the frosting, in the bowl of a standing mixer fitted with the paddle attachment, mix the cream cheese and butter for 5 minutes on medium speed to thoroughly smooth and aerate the frosting. Sift the confectioners’ sugar into a medium bowl and gradually add it to the cream cheese mixture. Add the lemon juice and mix for another 2 minutes, until the frosting is smooth and light. Hold it at room temperature until ready to use. (if it seems to warm and loose to hold its shape, refrigerate it, checking every 5 minutes and mixing with a rubber spatula until it looks spreadable.)
Spread the remaining ¼ cup of carrots on the prepared baking sheet in a single layer. Bake for 3 minutes to slightly dry them out, then toss with the remaining 2 tablespoons granulated sugar. Bake for another 8 to 10 minutes, until the carrots are crisp but not browned. (As they cool they will crisp up more.) Set aside to cool.
To assemble, place one cake layer on a serving plate. Place 1 ½ cups of frosting in the center of the cake and spread evenly, leaving a 1-inch unfrosted border around the edge; the frosting will be around 3/8 inch thick. Sprinkle the orange zest over the frosting. Set the other cake on top and level by gently pressing down on it.
If desired, at this point, you could crumb coat the cake. Cover the entire cake with a thin layer of frosting about 1/8 inch thick. The cake will still be visible through the frosting. Refrigerate the cake 20 minutes to firm it up, holding the remaining frosting at room temperature.
For the final coat use a layer of frosting no more than ¼ inch thick. First cover the sides of the cake; the frosting should be evenly distributed on the offset spatula so that you can coat the sides (top to bottom) all at once. Then frost the top, placing a dollop of frosting in the center and smoothing it out, squaring up the edges. Garnish by placing a 4-inch ring of baked carrots in the center of the cake and fill with the edible flowers.
You can store the baked cakes, unfrosted and well wrapped, in the freezer for up to 2 weeks. The frosted cake can be refrigerated for up to 4 days. Bring it to room temperature (about 2 hours) before serving.