From My Nepenthe Cookbook
Makes 1 Cake, Serving 10 to 12
2 cups cake flour
1 1/2 cups granulated sugar
2 teaspoons baking powder
1/2 teaspoon salt
6 eggs, separated, plus 1 egg white
1/2 cup vegetable oil
Zest and juice of 2 oranges (juice should equal 3/4 cup; add water if necessary)
2 tablespoons Grand Marnier
3/4 teaspoon cream of tartar
Simple Orange Glaze
1 tablespoons butter, softened
1 cup confectioners' sugar, sifted
2 teaspoons fresh orange juice
1 teaspoon hot water
1 teaspoon orange zest
1/2 teaspoon pure vanilla extract or Grand Marnier
Preheat the oven to 325°F. Have ready a 10-inch tube cake pan, preferably with a removable bottom. Do not grease or flour it.
For the cake, sift the flour, 1 1/3 cups of the granulated sugar, the baking power, and salt into a large bowl. Whisk the egg yolks with the oil in a medium bowl. Make a well in the dry ingredients and stir in the wet ingredients. Stir in the zest, juice, and Grand Marnier.
In a large, clean bowl, beat all the egg whites until frothy. Add the cream of tartar and remaining granulated sugar, and beat until stiff, but not dry, peaks form. Fold the whites into the batter until just blended.
Scrape the batter into the ungreased cake pan. Bake for 50 to 60 minutes, until the cake springs back to the touch. Immediately turn the cake over onto the neck of a bottle and let sit, undisturbed, until completely cool (at least 1 1/2 hours) before removing from the pan.
For the glaze, cream the butter in a small bowl using a wooden spoon. Add the confectioners' sugar, alternating with the juice and water. Beat until smooth. Stir in the orange zest and vanilla. The glaze should be thin enough to drizzle. If not, thin with a drop or two of hot water.
When the cake is cool, spread the top with the glaze, allowing it to drip down the sides.