Jean-Louis Palladin was a close friend and one of the greatest chefs I've ever known. And he made some of the best brioche I've ever tasted. This is his recipe. Start it a day before you want to make it, as the dough has to rest overnight. Mornay, a roux-thickened white sauce, is a luxurious cheese sauce that we use for gratineed scallops, macaroni and cheese, croque-monsieurs and -madames, and crepes. VARIATION: For 3 cups sauce, use 4 tablespoons (2 ounces) butter, 2/3 cup diced onion, 1/4 cup flour, 22/3 cups milk, 11/3 cups cream, 4 peppercorns, 4 cloves, and 1/2 cup cheese. Make the sauce in a large saucepan.