Croque Monsieur with Mornay Sauce

  • Active Time 30m
  • Total Time 50m
  • Rating ****

4 sandwiches

A traditional French croque monsieur sandwich is usually dipped into eggs then grilled on a sandwich-grilling iron. At my restaurant, Campanile, we serve this traditional French sandwich on bread from our bakery, La Brea Bakery, and with the added decadence of a creamy cheese sauce. - Nancy Silverton


  • For the Mornay Sauce:
  • 2 tablespoons butter
  • 1/4 cup finely chopped onion
  • Pinch of kosher salt
  • 1 bay leaf
  • 2 tablespoons all-purpose flour
  • 2 cups whole milk
  • 1/2 cup finely grated Gruyere cheese
  • 1/4 cup finely grated Parmigiano-Reggiano
  • 1 large egg yolk
  • For the Sandwiches:
  • 6 tablespoons unsalted butter
  • 8 slices fresh country-style white bread
  • 1 pound Gruyere cheese, sliced 1/16 inch thick (about 24 slices)
  • 12 ounces thinly sliced ham (about 16 slices)


Melt butter in heavy medium saucepan over medium heat. Add onion and pinch of salt. Saute until onion is tender and translucent, about 5 minutes. Add flour and stir 3 minutes (do not brown). Gradually whisk in milk. Add bay leaf. Simmer until sauce thickens, stirring occasionally, about 5 minutes. Season with salt and pepper. Cool to lukewarm, about 30 minutes.

Gradually add cheese and stir until completely melted. Remove Mornay sauce from heat. Lightly beat egg yolk in small bowl. Whisk 1 tablespoon of Mornay sauce into egg. Fold egg mixture into Mornay sauce. Cover to keep sauce warm.

Spread 1/2 tablespoons butter on one side of each bread slice. Place 4 bread slices on work surface, buttered side down. Divide half of cheese among bread slices. Place ham slices atop cheese, dividing evenly. Top with remaining cheese. Top sandwiches with remaining 4 bread slices, buttered side up.

Heat griddle or cast iron skillet over medium heat. If using a griddle, cook sandwiches until bottom is golden brown and cheese is melted, about 3 minutes per side. If using a cast iron skillet, cook sandwiches until golden brown, about 3 minutes. Turn sandwiches over, then place skillet in 400 degrees F. oven, until golden brown on bottom and cheese is melted, about 5 minutes.

Place sandwiches on a heatproof plate or baking sheet. Spoon 1/4 cup sauce over each sandwich. Broil until sauce is pale golden and bubbles, about 2 minutes. Serve immediately.

Recipe reprinted by permission of Publisher. All rights reserved.

RecID 4340

nutrition information per serving

1156 calories; 78g total fat; 316mg cholesterol; 2231mg sodium; 49g carbohydrates; 4g fiber; 68g protein

These nutrition facts are calculated according to the ingredients listed in this recipe. Any substitutions will change these facts. Although we strive for accuracy, please note that food manufacturers occasionally change their food formulas, which could affect the calculations as shown.

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