Ingredients

FILLING:3-1/2 cups cold whole milk2 packages (3.4 ounces each) instant lemon pudding mix1 teaspoon grated lemon zestCAKE:6 large egg whites1 cup butter, softened3 cups sugar3 teaspoons vanilla extract4 cups cake flour1 teaspoon baking soda1/2 teaspoon baking powder1/2 teaspoon salt2 cups buttermilkFROSTING:1 cup sugar2 large egg whites, room temperature1/2 cup water1/4 teaspoon salt1/8 teaspoon cream of tartar1/4 teaspoon vanilla extract2 cups sweetened shredded coconut

Preparation

In a large bowl, whisk milk, pudding mix and zest 2 minutes. Cover and refrigerate at least 1 hour.

Place egg whites in a large bowl; let stand at room temperature 30 minutes. Preheat oven to 350°. Line bottoms of three greased 9-in. round baking pans with parchment; grease paper.

In a large bowl, cream butter and sugar until light and fluffy. Beat in vanilla. In another bowl, whisk flour, baking soda, baking powder and salt; add to creamed mixture alternately with buttermilk, beating well after each addition. With clean beaters, beat egg whites on high speed until stiff peaks form; gently fold into batter.

Transfer to prepared pans. Bake 25-30 minutes or until a toothpick inserted in center comes out clean. Cool in pans 10 minutes before removing to wire racks; remove paper. Cool completely.

For frosting, in a large heavy saucepan, combine sugar, egg whites, water, salt and cream of tartar over low heat or in a double boiler over simmering water. With a portable mixer, beat on low speed 1 minute. Continue beating on low over low heat until frosting reaches 160°, about 12 minutes.

Pour into the bowl of a heavy-duty stand mixer; add vanilla. Beat on high until frosting forms stiff peaks, about 7 minutes.

Using a long serrated knife, cut each cake horizontally in half. Place one cake layer on a serving plate; spread with 3/4 cup filling to within 1-inch of edge. Repeat four more times. Top with remaining cake layer. Frost top and sides of cake. Sprinkle top with coconut; gently press coconut into frosting on sides of cake. Store in the refrigerator.