Croque-Madame, Sauce Mornay (Grilled Ham and Cheese Sandwich with a Fried Egg and Mornay Sauce)

  • Recipe courtesy of Chef Thomas Keller at Bouchon in Las Vegas
  • Show: Giada's Weekend Getaways
  • Episode: Las Vegas
Total Time:
16 hr 35 min
1 hr 40 min
Inactive Prep:
14 hr 35 min
20 min
4 servings


  • 8 (1/2-inch-thick) slices Brioche, recipe follows or other egg bread, or pain de mie (about 4 inches square)
  • 8 ounces thinly sliced boiled ham
  • 8 slices (about 1/2-ounce each) Swiss cheese
  • 3 tablespoons unsalted butter
  • 4 large eggs
  • 1 cup Mornay Sauce, warmed, recipe follows
  • Brioche
  • 3 tablespoons unsalted butter
  • 1/2 cup diced (1/4-inch) Spanish onion
  • Kosher salt
  • 3 tablespoons all-purpose flour
  • 2 cups milk
  • 1 cup heavy cream, or as needed
  • 1 bay leaf
  • 3 black peppercorns
  • 3 whole cloves
  • Freshly grated nutmeg
  • Freshly ground white pepper
  • 1/3 cup grated Comte or Emmentaler cheese
  • Mornay Sauce
  • 1/3 cup very warm water (110 degrees to 115 degrees F)
  • 1 (1/4-ounce) package active dry yeast (not quick-rising)
  • 10 1/2 ounces (2 1/2 cups) cake flour
  • 10 ounces (2 cups) all-purpose flour
  • 1/3 cup sugar
  • 2 1/2 teaspoons fine sea salt
  • 6 large eggs, at room temperature
  • 20 tablespoons (10 ounces) unsalted butter, cut into 1-inch cubes, at room temperature, plus butter for the pans


Preheat the oven to 375 degrees F.

Lay out the bread slices. Divide the ham among them, making sure it doesn't extend over the edges of the bread. Place the cheese over the ham. If the cheese is larger than the bread, bend it over to fit.

Heat 2 large ovenproof nonstick pans or griddles over medium heat. (If you have only 1 large pan, make 2 sandwiches and keep them warm in the oven while you make the second batch.) Add 1 tablespoon of the butter to each pan. When it has melted, add half the bread, cheese-side up to each pan and cook for 1 to 2 minutes, or until the bottoms are golden brown. Transfer the pans to the oven for 2 to 3 minutes to melt the cheese.

Meanwhile, melt the remaining 1 tablespoon of butter in a large ovenproof skillet and fry the eggs. Cook the eggs until the bottoms are set, then place the skillet in the oven for a minute to set the