Sweet Potato Cake with Chocolate Cream Cheese Frosting

The autumn equinox (September 22 for 2010) is a day that can easily pass us by without thought. The summer and winter solstices are more obvious and likely to be noticed. The spring and autumn equinoxes mark the midpoints between solstices and are the days when day and night, light and dark, are equal in length. In autumn, the journey into winter starts picking up speed.

I personally feel that autumn deserves a special cake. And this cake showcases all the glory and splendor of the season. Enjoy!

Ingredients for Cake:
2 medium or 1 large sweet potato (about 12 ounces)
3 cups cake flour
3 teaspoons baking powder
1 & 1/2 teaspoons ground cinnamon
3/4 teaspoon grated nutmeg
1/4 teaspoon ground cloves
5 eggs, separated
2 & 1/4 cups sugar
1 stick plus 2 tablespoons (5 ounces) unsalted butter, at room temperature
1 & 1/2 teaspoons vanilla extract
1 & 1/4 cups milk

Directions for the Cake:
1. Preheat the oven to 400 degrees. Prick the sweet potatoes in 2 or 3 places, set in a small baking dish, and bake for 1 hour, or until the potatoes are very soft and their juices are oozing. Remove from the oven and let cool slightly. The batter comes together more easily when the potato puree is warm.

2. Reduce the oven temperature to 350 degrees. Butter the bottoms and sides of three 9-inch round pans. Line with rounds of parchment or waxed paper and butter the paper.

3. As soon as the sweet potatoes are cool enough to handle, peel off the skin and remove any dark spots. Cut the potatoes into chunks and put into a food processor. Puree until smooth. Measure out 1 cup sweet potato puree for this recipe. Any leftover is cook's bonus.

4. Sift together the flour, baking powder, cinnamon, nutmeg, and ground cloves. Set these dry ingredients aside.

5. In a large mixer bowl with and electric mixer on medium speed, beat the egg whites until frothy. Raise the speed to high and gradually beat in 1/4 cup of the sugar. Continue to beat until the egg whites form moderately stiff peaks.

6. In another large bowl, combine the sweet potato puree, softened butter, vanilla, and the remaining 2 cups sugar. Beat until the mixture is light and fluffy. Add the egg yolks one at a time, beating well and scraping down the sides of the bowl after each addition. With the mixer on low speed, add the dry ingredients and milk alternately in 2 or 3 additions, beginning and ending with the dry ingredients. (If using a hand mixer, you'll probably need to use medium-low speed.)

7. With a large rubber spatula, fold in one-fourth of the beaten egg whites to lighten the batter. Then fold in the remainder just until no streaks remain, be sure not to over-mix or the batter will deflate. Divide the batter among the 3 prepared cake pans.

8. Bake for 25 to 30 minutes, or until a cake tester or wooden toothpick stuck in the center comes out clean and the cake is beginning to pull away from the sides of the pan. Let the layers cool in their pans for 10 minutes. Then turn out onto wire racks, peel off the paper liner, and let cool at least 1 hour.

9. To assemble the cake, put one layer, flat side up, onto a cake stand or serving plate. Fit a pastry bag with a 1/2-inch plain tip and fill with about 1 cup of the Chocolate Cream Cheese Frosting. Pipe a border around the top edge of the cake to create a rim. Fill the center with half the Orange Cream Filling, smoothing it to the chocolate border. Place a second layer on top of the filling, and pipe a border of frosting around it. Fill with the remainder of the filling, again smoothing it to the border. Place the third layer on top of all and use the rest of the frosting to cover the sides an top of the cake.

Ingredients for Chocolate Cream Cheese Frosting:
10 ounces cream cheese, at room temperature
1 stick (4 ounces) unsalted butter, at room temperature
1 box (16 ounces) confectioner's sugar, sifted
1 & 1/2 ounces unsweetened chocolate, melted and cooled slightly

Directions for Chocolate Cream Chesse Frosting:
1. In a large mixer bowl, beat together the cream cheese and butter until well blended. Gradually add the confectioners' sugar in batches, sifting or shaking it through a sieve and scraping down the sides of the bowl several times. Beat until the mixture is light and fluffy, 2 to 3 minutes.

2. Measure out 1 cup of the sweetened butter and cream cheese and set aside for the orange cream frosting.

3. Beat the melted chocolate into the remainder of the cream cheese mixture until thoroughly incorporate. Use at once.

Ingredients for Orange Cream Filling:

1 cup sweetened cream cheese and butter mixture, reserved in step 2 of the Chocolate Cream Cheese Frosting (recipe above)

2 tablespoons frozen orange juice concentrate, thawed

1/4 teaspoon orange extract

Directions for Orange Cream Filling:
1. Stir together the sweetened cream cheese and butter, orange juice concentrate, and orange extract until well blended.