Hail to the chef: Former White House pastry guru shares his sweet secretsImagine spending almost 25 years in the White House pastry kitchen as the executive pastry chef for five presidents and first families, doing your work surrounded by pounds of butter, chocolate, cream, fresh fruits and sugar. While the job may sound like a dessert lover's dream, it's not always as sweet as it seems. Just ask French-born patissier Roland R. Mesnier, who retired last July. Lately he's been traveling throughout the country promoting his first cookbook, "Dessert University" (Simon & Schuster; $40), which took four years to write...