A quintessential French bistro delight, this simple and elegant croque monsieur will have you dreaming of dining on the cobbled streets of Paris. Adopting the form of a , these crispy, hot ham and cheese sandwiches are on the table in under one hour, with plenty of time to toss together a side or pop some in the air fryer. For the full French bistro effect, end the meal with some easy, fruit-stuffed !
What is a croque monsieur?
This dish is much more than an elevated ham and cheese sandwich. While the inside simply has ham, gruyère cheese, and dijon mustard, the dreamy bechamel sauce—the very same butter, flour, and milk mixture that forms the base for
—is what sets this sandwich apart from the rest. This sauce is spread both on the inside of the sandwich and all over the top of it. A final sprinkle of gruyère is all this saucy sandwich needs before it goes under the broiler to get its characteristically melty, blistered top. To transform this sandwich into its equally famous counterpart, the croque madame, simply serve it with a poached or fried egg on top.
Can a croque monsieur be made in advance?
This sandwich can be reheated in an oven with delicious results, but it tastes its absolute best just after assembly. You can, however, make the bechamel sauce ahead of time.
The bechamel sauce can be made all the way through and placed in an airtight container with a layer of plastic wrap pressed directly on the surface of the sauce, so that it doesn’t form a skin. It can be fully cooled and stored in the refrigerator for up to 5 days.
4 tbsp. salted butter
1/4 c. all-purpose flour
1/4 tsp. kosher salt, plus more to taste
1/4 tsp. ground black pepper, plus more for sprinkling
Pinch ground nutmeg
2 c. warm milk
6 tbsp. salted butter, at room temperature
12 slices hearty white sandwich bread
2 tbsp. dijon mustard
3/4 lb. ham, sliced (at least 12 slices)
1 lb. gruyère cheese, shredded and divided
1 tbsp. chopped fresh chives, for sprinkling
Step 1 Preheat the oven to 375°F.
Step 2 For the bechamel sauce: In a medium saucepan, heat the butter over medium heat until melted and the foaming subsides. (Do not let it brown.) Whisk in the flour, salt, pepper, and nutmeg until well combined. Cook, whisking constantly, until the raw flour smell disappears, 1 to 2 minutes. Slowly stream in the warm milk, whisking constantly until no lumps remain. Continue whisking over medium heat and occasionally scraping the bottom and sides of the saucepan with a rubber spatula until the sauce thickens to a pudding-like texture, 4 to 5 minutes.
Pour the sauce into a medium bowl and place a piece of plastic wrap directly on the surface so it does not form a skin.
Step 3 For the sandwiches: Evenly spread about 1/2 tablespoon of butter on 1 side of each slice of bread. Place 6 slices, butter-side down, on a rimmed baking sheet. Evenly spread about 1 teaspoon of dijon mustard on each slice of bread on the baking sheet. Place 2 folded slices of ham on top of the mustard. Sprinkle the ham with about ½ cup (2 ounces) of the cheese. Spread about 1 tablespoon of bechamel sauce on the unbuttered side of the remaining 6 slices of bread. Place the bread, bechamel-side down, on top of the cheese.
Step 4 Bake the sandwiches on the center rack of the oven until the bread is lightly golden and the cheese is starting to melt, 6 to 8 minutes. Remove the baking sheet from the oven and carefully flip the sandwiches. Bake the other side until lightly golden, about 6 minutes. Remove the baking sheet and increase the oven temperature to broil.
Step 5 Spoon about 3 tablespoons of bechamel sauce on each of the sandwiches, spreading to completely cover the top slice of bread. Sprinkle about 2 tablespoons (½ ounce) of the remaining cheese on each sandwich, topping the bechamel.
Step 6 Broil the sandwiches on the center rack of the oven, watching carefully and rotating the baking sheet as needed, until the cheese is bubbling and beginning to brown, 1 to 4 minutes.
Step 7 Sprinkle the sandwiches with fresh chives and pepper, and serve hot.
