A croque-monsieur is a grilled ham and cheese sandwich that originated in France. After grilling, the sandwich is typically covered with a Bechamel or Mornay sauce. Some recipes may call for cheese to be melted on the top of the sandwich in place of a sauce. The sandwich is grilled by buttering both pieces of bread and then cooking it in a hot skillet until the cheese inside is melted, and the outside of the sandwich is crispy. Traditionally, high-quality sliced ham and cheese, such as Gruyere or Emmantal, is used, but there are many variations of this recipe.
When making a croque-monsieur, thick-sliced, artisanal bread is typically used. A thicker slice of bread tends to stand up better to being topped with a cream sauce. The outer side of each bread slice is covered with butter to help make it crisp and golden during cooking. Several slices of ham and one or two slices of cheese are placed between the bread. Some variations of the recipe may call for mustard, or a small amount of Bechamel or Mornay sauce, to be spread on the inside of the sandwich.
For best results, high-quality ham and cheese should be used. Sliced ham can be purchased in a deli, and may come in different flavors, such as smoked or honey-roasted. Any type of ham can be used to make a croque-monsieur. A less traditional variation of the recipe may use turkey or another type of thin-sliced deli meat.
Traditionally, Gruyere or Emmantal cheese is used to make a croque-monsieur. Swiss cheese is also commonly used. Any type of cheese that tends to melt smoothly can be added to this sandwich. If melting cheese on top of the sandwich instead of using a sauce, the cheese is placed on the bread and melted under a broiler.
The Bechamel sauce for a croque-monsieur is made with flour, milk, butter, nutmeg, and a bay leaf. A roux is made with the butter and flour, and the rest of the ingredients are then added to a saucepan. As the sauce cooks, it thickens. A Mornay sauce is very similar to a Bechamel, but includes cheese in its ingredients.
Croque-monsieur sandwiches are very popular menu items in French bistros and cafes. They can be served at any meal of the day, and are often also eaten as a snack. This type of sandwich is usually eaten with a knife and a fork, particularly if it has a cheese or sauce topping.