Croque Monsieur Recipe (Toasted Ham and Cheese Sandwich)

Ingredients

• 14 g (1 tablespoon)salted butter
• 8 g (1 tablespoon)plain flour
• 360 ml (1½ cups)whole milk
• 4 thick slicesFrench bread
• 0.6 ml (⅛ teaspoon)ground nutmeg
• 0.6 ml (⅛ teaspoon)ground black pepper
• about 113 g (2 cups grated; about 4 oz), dividedGruyère cheese
• 113 g (4 oz), slicedsmoked ham
• 10 ml (2 teaspoons)Dijon mustard

Instructions

1. 1

   Preheat the oven

   Heat the oven to 204°C (400°F).

2. 2

   Make the béchamel

   Melt the butter in a small saucepan over medium-low heat. When it begins to bubble, whisk in the flour and cook for 2–3 minutes, until smooth and bubbling. Slowly pour in the milk while whisking continuously, then cook and whisk for another 4–5 minutes, until thick.

3. 3

   Toast the bread

   Meanwhile, toast the bread in the preheated oven for 3–4 minutes on each side.

4. 4

   Season the sauce

   Turn off the heat and stir the nutmeg, black pepper and one-third of the cheese into the thick sauce. Set it aside.

5. 5

   Assemble sandwiches

   Take the bread out of the oven and spread 1 teaspoon of mustard over two slices. Add half the ham, then half of the remaining cheese. Top each with another slice of bread and set the sandwiches on a grill rack over a baking sheet. Pour the sauce over the tops and bake for 5 minutes.

6. 6

   Broil and serve

   Switch off the oven and turn the grill to high. Grill for 2–3 minutes, until the sauce is bubbling and browned on top. Serve warm.

What is a croque monsieur?

A croque monsieur is a French hot ham and cheese sandwich, typically finished with béchamel and a crisp, browned cheese topping. Its name is often associated with the idea of a sandwich that is crunched or toasted.

This version layers smoked ham and Gruyère between toasted French bread, then covers the sandwiches with a nutmeg-seasoned white sauce. Toasting the bread first helps it hold up beneath the sauce.

Nutrition and macros by portion

The nutrition label shows one serving as written: 578 calories, 37g protein, 33g carbs, 33g fat.

The bread supplies most of the carbohydrates, while butter, milk and Gruyère contribute much of the fat. Ham, cheese and milk provide protein. Pair a sandwich with a green salad or other vegetables to add freshness and balance the plate.

Building the béchamel

Roux: Let the butter bubble, then whisk in the flour and cook it for 2–3 minutes. This gives the sauce its base and helps avoid a raw flour taste.

Milk: Add it gradually while whisking so the mixture stays smooth. Keep cooking until the sauce thickens enough to coat the back of a spoon.

Choosing the ingredients

Gruyère: Its savoury flavour works both in the sauce and in the filling. The recipe divides the cheese between those layers and the topping.

Smoked ham: Sliced ham is easy to layer and brings a savoury, smoky note. Dijon mustard adds a sharp contrast beneath it.

Getting the texture right

Bread: Give the slices 3–4 minutes on each side in the oven before assembling. They should be lightly toasted rather than deeply browned, as they will bake again.

Topping: Watch closely during the final 2–3 minutes under the grill. The sauce should bubble and develop browned patches without scorching.

Timing the stages

Sauce first: Make the béchamel while the oven heats and the bread toasts. This keeps the assembly moving while the sauce is still easy to pour.

Final finish: The assembled sandwiches bake for 5 minutes before grilling. Allow for the short grill stage, which browns the topping and finishes the dish.

What to serve alongside

A simple green salad with a sharp vinaigrette is a fresh counterpoint to the creamy sauce and melted cheese. For a heartier meal, serve with a light vegetable soup.

Serve the sandwiches as soon as they come out from under the grill, while the topping is still bubbling and the bread remains crisp.

Recipe notes & tips

• Whisk continuously as you pour in the milk to keep the béchamel smooth.
• Use a small saucepan so the butter and flour are easy to whisk together.
• Keep the bread slices together as pairs so each sandwich has a base and a lid.
• Set the grill rack over a baking sheet to catch any sauce that runs off.
• Stay by the oven during grilling, as the cheese topping can brown quickly.

Variations

• Use another melting cheese: Replace Gruyère with Comté or Emmental for a different flavour.
• Make a croque madame: Top each finished sandwich with a fried egg.
• Add herbs: Stir a little chopped thyme into the béchamel for an aromatic note.
• Try unsmoked ham: Use plain cooked ham for a milder filling.
• Use sourdough: Swap in thick slices of sourdough bread for a tangier base.

Common mistakes to avoid

• Adding milk too quickly: Pour it in gradually while whisking to help prevent lumps.
• Undercooking the roux: Cook the flour and butter for the full 2–3 minutes before adding milk.
• Skipping the first toast: Toast both sides of the bread so it holds up better under the sauce.
• Overfilling the sandwiches: Keep the ham and cheese in an even layer so the bread sits neatly.
• Leaving the grill unattended: Check frequently during the final 2–3 minutes to prevent the topping from burning.

How to store

Store leftovers covered in the fridge and eat within 2 days. Reheat in an oven until hot throughout; the bread may be less crisp after storage.

Frequently asked questions