Ingredients:
Cake:
2 cups sifted cake flour**
1 1/2 tsp. baking powder
1/2 tsp. Cream of tartar
9 large eggs, separated
2 cups sugar
1/2 cup vegetable oil
2 tsp. grated lemon rind
2 Tbsp. lemon juice
1/8 tsp. Salt
Orange-lemon frosting:
1/2 cup butter, softened
2 T sour cream
32 oz. powdered sugar, sifted
1/4 cup grated orange rind (~ 4 oranges)
1 Tbsp. plus 1 tsp grated lemon rind (~ 2 lemons)
3-4 Tbsp. orange juice
2 Tbsp. lemon juice
Directions:
Cake:
Grease and flour 8 “ round cake pans. Line with wax paper; grease paper, and set aside.
Combine first 3 ingredients; stir well. Combine egg yolks and sugar in a large mixing bowl; beat at high speed of an electric mixer until thick and lemon colored. Gradually add oil, beating at medium speed. Add flour mixture, mixing until blended. Stir in lemon rind and juice. Set aside.
Beat egg whites and salt at high speed until stiff peaks form. Gently stir one-forth of egg white mixture. Pour batter into prepared pans.
Bake at 325 degrees for 20 to 25 minutes or until a wooden toothpick inserted in center comes out clean. Let cool in pans 10 minutes. Remove from pans; peel off wax paper, and let cool completely on wire racks.
Frosting:
Mix butter and sour cream in mixer and slowly add some of 10x sugar. Add the rest of ingredients and mix until smooth and spreadable consistency. After cake is cooled, spread orange-lemon frosting between layers, on sides, and on top.
**Note: To make GF cake flour:
For every 1 cup (120g) unbleached cake flour called for in a recipe:
- Whisk together 3/4 cup + 2 tablespoons (105g)GF 1:1 flour and 2 tablespoons (14g) cornstarch.
The cornstarch adds tenderness and lowers the overall protein content of the mixture to mimic that of cake flour.