Layers of light, lemon-flavored buttermilk cake alternate with lemon-meringue buttercream and fresh blueberries. It's a perfect choice for summer, though you don't have to wed in June to serve it. "In the U.S. blueberries grow from May to July," says baker Jim Smeal, of Wedding Cakes by Jim Smeal in Charleston, S.C, who created Reese Witherspoon's wedding cake. "But now you can get almost anything you want any time of year, if you pay a little bit more."