Ingredients

  • 2 14 cups sifted cake flour
  • 2 12 teaspoons baking powder
  • 12 teaspoon salt
  • 12 cup unsalted butter
  • 1 teaspoon freshly grated lemon zest
  • 12 teaspoon freshly grated navel orange rind
  • 1 13 cups superfine sugar or 1 13 cups strained sugar
  • 3 large eggs
  • 13 cup water
  • 3 tablespoons fresh lemon juice
  • 14 cup fresh orange juice
  • 1 tablespoon powdered sugar, for garnish

Method

  • Position oven rack in lower third of oven; preheat to 350; butter a 13x9 inch baking pan.
  • Using a triple sifter, sift together the flour, baking powder, and salt; set aside.
  • Cut the butter into 1-inch pieces and place in the large bowl of a stand mixer with paddle attachment.
  • Add in the lemon and orange rinds and soften on low speed.
  • Increase to med-high and cream until smooth and light in color, about 1 1/2-2 minutes.
  • Add the sugar 1 tablespoon at a time, taking about 6-8 minutes to blend it in well.
  • Scrape the sides of the bowl occasionally.
  • Add in eggs, 1 at a time at 1-minute intervals, scraping down the sides of the bowl as needed.
  • Decrease speed to low; in a small bowl, combine the water, lemon juice, and orange juice.
  • Add the dry ingredients alternating with the liquids, dividing the flour mixture into 3 parts and the liquid into two parts, starting and ending with the flour.
  • Mix just until incorporated after each addition; do not worry if the batter appears to curdle, it should smooth out after the flour is blended inches.
  • Scrape the sides of the bowl and mix for 10 seconds longer.
  • Spoon batter into prepared pan, smoothing with the back of a spoon.
  • Center the pan on the oven rack and bake for 30-35 minutes, or until the cake is golden brown on top, springy to touch, and begins to come away from the sides of the pan.
  • Remove pan from oven and set on a cake rack to cool.
  • Just before serving, place powdered sugar in a fine mesh strainer and dust the top of the cake; cut into squares and serve.