Recipes Ingredients Meat & Poultry Pork Recipes Rustic Croque Monsieur 3.1 (45) 3 Reviews By Martha Stewart Martha Stewart Martha Stewart is a bestselling author, entrepreneur, and lifestyle expert who has taught millions of people through generations the joy of entertaining, cooking, gardening, collecting, crafting, and home renovating via her eponymous magazine, Martha Stewart Living, Emmy-winning television shows, and 99 books (and counting). Based in Katonah, N.Y., where she helms her 156-acre Bedford Farm, Martha is America's first self-made female billionaire. Editorial Guidelines Updated on July 8, 2019 Rate PRINT Share Close Prep Time: 5 mins Total Time: 35 mins Yield: 4 Parmesan cheese helps gives this French sandwich its salty flavor. Ingredients 2 tablespoons unsalted butter, plus more for bread 2 tablespoons all-purpose flour 2 cups whole milk ½ cup grated Gruyere cheese, plus 8 slices ½ cup grated Parmesan cheese 8 thick slices rustic bread 12 slices ham Dijon mustard, for bread Directions Melt butter in a saucepan over medium heat. Whisk in flour. Add milk; bring to a simmer. Cook, whisking frequently, until sauce thickens, about 5 minutes. Remove from heat. Add grated cheeses. Whisk until melted and smooth. Butter bread. Arrange half the slices, buttered side down, on a rimmed baking sheet. Top each with 2 slices Gruyere and 3 slices ham. Spread mustard onto unbuttered sides of remaining bread. Place on top of ham, buttered side up. Preheat broiler. Heat a grill pan or skillet over medium heat. Cook each sandwich until golden brown and cheese melts, about 5 minutes per side. Return to baking sheet. Spoon 1/3 cup sauce over top of each sandwich. Broil until tops are bubbling and golden brown, about 3 minutes. Originally appeared: Martha Stewart Living, February 2010 Rate It PRINT