"Tackling this ambitious four-layer cake is worth the impressive results for a special birthday party or family gathering. To start, make the tangy lemon-lime curd with citrus juice, zest, sugar, and egg yolks. Then spread the curd between layers of citrusy white cake and frost the whole thing with airy whipped cream. Finally, decorate the sides and top with candied lemon and lime zest for a triple dose of citrus. What to buy: For this recipe, use bleached cake flour such as Softasilk, for a tender cake that will rise high and evenly. Don’t use unbleached cake flour, which yields denser results. Game plan: The lemon-lime curd and candied zest can be made up to 3 days ahead. This recipe was featured as part of our birthday cake recipe gallery...."