Sauce creates the depth of a dish, like a perfume does to a person,” says chef Arnaud Donckele, presiding over the dining room at La Vague d’Or, his restaurant at the Cheval Blanc hotel in St. Tropez. He’s a soft-spoken voice in the world of haute cuisine, but when he speaks up, it matters. A reservation at La Vague d’Or is the most difficult one to secure on the French Riviera. (It’s also a serious slog to book a table at Plénitude, his restaurant at the Cheval Blanc hotel in Paris.) He poetically describes his Paris restaurant as “porcelain, and St. Tropez is pottery.” And yet a magnificent dinner I enjoyed recently proved that it’s well worth moving heaven and earth to eat there. —Alexander Lobrano