2 teaspoons baking powder
2 cups (8 ounces) white whole-wheat flour; see cook's notes
1/2 teaspoon salt
5 large egg yolks (save the whites)
1/2 cup vegetable oil
1 1/2 cups sugar
1/3 cup water
1/4 cup fresh grapefruit juice
1 tablespoon freshly grated grapefruit zest (colored part of peel)
5 large egg whites
1/4 teaspoon cream of tartar
2 packages (16 ounces total) cream cheese, softened
3 cups (12 ounces) sifted powdered sugar
2 teaspoons freshly grated grapefruit zest (colored part of peel)
1 teaspoon freshly grated lemon zest (colored part of peel)
1 tablespoon fresh grapefruit juice
1 teaspoon fresh lemon juice
Garnish: 1 grapefruit, peeled, cut into sections
For serving: vanilla ice cream
Yield: 16 servings
1. Preheat oven to 350 degrees. Lightly grease two 9-inch cake pans, line with parchment paper or wax paper; grease paper.
2. Whisk flour, baking power and salt in medium bowl; set aside.
3. Combine egg yolks and oil in large mixing bowl and mix at low speed while gradually pouring in sugar. Add water, grapefruit juice; beat 20 seconds. Add dry ingredients. Beat 3 minutes on medium speed, then stop and scrape down sides and bottom of bowl. Mix in grapefruit zest.
4. In separate bowl with clean beaters, beat egg whites until foamy. (Any grease left on beaters will keep eggs from whipping to their proper volume). Add cream of tartar and continue beating until soft peaks form. Carefully fold beaten egg whites into cake batter. Divide batter evenly between pans. Bake until top of cake pulls away from edge of pan, and a toothpick inserted in center comes out clean, 20 to 25 minutes.
5. Remove cakes from oven and run a dinner knife around edge of each cake. Cool cakes in pans for 10 minutes. After 10 minutes, remove layers from their pans and peel off paper. Cool completely on wire racks, then refrigerate or freeze before frosting.
6. To make frosting, blend cream cheese and powdered sugar in large bowl until smooth (or use food processor, pulsing to combine). Add grated zests and juices; beat until smooth.
7. Place one layer of cake on cake plate. Spread with about 2/3 cup of frosting. Top with second layer. Frost top and sides of cake with remaining frosting and garnish with grapefruit segments. Serve with vanilla ice cream.
Cook's notes: King Arthur white whole-wheat flour is sold at Trader Joe's and some supermarkets
Nutritional information (per serving): calories 260 (79 percent from fat), protein 3.1 g, carbohydrates 37 g, fat 11 g (saturated 6 g), cholesterol 65 mg, sodium 450 mg, fiber 1.5 g