This recipe is the “Citrus Surprise Cake” in the King Arthur Flour Whole Grain Baking book by The King Arthur Flour Company, Inc.; ISBN-13 978-0-88150-719-5; ISBN-10 0-88150-719-9.
I have just been making this as a flat rectangular cake and using 1/2 the frosting called for in the recipe, and it’s GREAT!! I am curious to see how it would taste as a regular 9-inch 2-layer cake.
- 2 c (8 ounces) white whole wheat flour (regular whole wheat works fine too)
- 2 tsp baking powder
- 1/2 tsp salt (I usually omit this)
- 5 large (2-1/2 ounces) egg yolks
- 1/2 c (3-1/2 ounces) vegetable oil
- 1-1/2 c (10-1/2 ounces) granulated sugar (I used demerara for this)
- 1/3 c (2-5/8 ounces) water
- 1/4 c (2 ounces) fresh grapefruit juice
- 1 Tbsp freshly grated grapefruit zest
- 5 large (6-1/4 ounces) egg whites
- 1/4 tsp cream of tartar
- 2 packages (16 oounces) cream cheese, softened (light cream cheese works well too)
- 3 c (12 ounces) sifted confectioner’s sugar (demerara makes this a crunchier but tastier frosting)
- 2 tsp freshly grated grapefruit zest
- 1 tsp freshly grated lemon zest
- 1 Tbsp fresh grapefruit juice
- 1 tsp fresh lemon juice
- Can use 1 grapefruit for garnish (optional)
Preheat oven to 350 F.
Lightly grease two 9-inch cake pans, line with parchment or wax paper, then grease the paper.
Whisk together the flour, baking powder and salt in bowl 1. Set aside.
Combine egg yolks and oil in large mixing bowl (bowl 2) and mix at low speed while you pour in the sugar. Add the water and grapefruit juice. Beat for 3 minutes at medium sped, then stop to scrape the sides and bottom of the bowl. Mix in the grapefruit zest.
Gently fold in the flour mixture (from bowl 1) into the mixing bowl (bowl 2) with rubber spatula or whisk.
In a separate bowl (bowl 3) with clean beaters, beat egg whites until foamy. Add the cream of tartar, and continue beating until soft peaks form.
Carefully fold the beaten egg whites (bowl 3) into the other mixture (bowl 2).
Divide the batter evenly between pans. Bake until the top of the cake pulls away from the edges of the pan, and a toothpick inserted in the center comes out clean, 20-25 minutes.
Remove from the oven, and run a dull knife around the edge of the cake to free the edges. Cool in the pan for 10 minutes, then remove from pan and peel off parchment paper. Cool completely on wire racks, then refrigerate or freeze before frosting.
Blend together the cream cheese and sugar in large bowl until smooth. Add grated zests and juices, beat until smooth.