Lemon Poppy Seed Chiffon Cake

To prepare cake: Preheat oven to 350 degrees F.

Whisk whole-wheat flour, cake flour, 1/3 cup sugar, poppy seeds, baking powder and salt in a large bowl. Whisk milk, oil, egg yolks, 2 tablespoons lemon zest and vanilla in a medium bowl.

Beat egg whites with an electric mixer, preferably in a stand mixer with the whisk attachment, until frothy and the whisk leaves a trail in them, 1 to 3 minutes. Slowly add the remaining 1/3 cup sugar and continue to beat until the whites are a bit glossy and hold a soft peak when you raise the whisk, 2 to 3 minutes more.

Make a well in the center of the dry ingredients and pour in the wet ingredients; stir with a rubber spatula to combine. Fold in a few large spoonfuls of the egg whites. Add the rest of the whites and fold gently until well combined. Scrape the batter into an ungreased 9-inch tube pan with a removable bottom.

Bake the cake until it is pale golden brown and springs back when you poke it in the middle, 40 to 50 minutes. Cool upside down in the pan on a wire rack, about 2 hours. When cool, run a knife around the sides and bottom of the pan to remove the cake.

To prepare glaze: Just before serving, whisk confectioners' sugar, lemon zest and lemon juice in a small bowl. Drizzle the cake with the glaze; garnish with more lemon zest, if desired.