FOR THE CAKE:

Unsalted butter, at room temperature, for the pan

2 cups all-purpose flour, plus more for the pan

2 teaspoons baking powder

2 teaspoons baking soda

2 teaspoons ground cinammon

1 teaspoon salt

3/4 cup vegetable oil

4 large eggs

Grated zest and juice of 1 orange

3/4 cup granulated sugar

2/3 cup packed light brown sugar

3 cups grated raw parsnips

1 cup hazelnuts, toasted and roughly chopped

FOR THE FROSTING:

6 tablespoons (3/4 stick) unsalted butter, at room temperature

1/3 cup confectioners' sugar, plus more for dusting

1 (8-ounce) block of cream cheese

1/3 cup apricot jam

MAKE THE CAKE: Preheat the oven to 375°F. Butter two 10-inch springform pans, line the bottoms with parchment paper, and butter and flour the paper and sides, tapping out excess flour.

Combine the flour, baking powder, baking soda, cinnamon, and salt in a medium bowl.

In a stand mixer fitted with the paddle attachment. combine the vegetable oil, eggs, orange zest and juice, granulated sugar, and brown sugar. Mix on low until smooth. Add the dry ingredients and mix on low speed until just blended, scraping down the sides of the bowl with a spatula as needed. Add the parsnips and hazelnuts and mix until just incorporated.

Divide the batter between the two pans and bake until a cake tester or knife inserted into the center comes out clean, 20 to 25 minutes. Let the cakes cool in the pans on a wire rack.

MAKE THE FROSTING: In a stand mixer fitted with the paddle attachment, beat the butter until fluffy and pale, about 1 minute. Add the confectioners' sugar and beat again for another minute. Add the cream cheese and jam and mix just until incorporated.

Remove the sides of the springform pans. Put one of the cakes upside down on a cake stand and remove the parchment paper. Spread the frosting over the cake. Top with the second cake, remove the parchment and dust with confectioners' sugar. You can refrigerate any leftovers for a day or two, but they won't last that long.