Classic Croque Monsieur

Name: Classic Croque Monsieur Recipe
Prep time: 10 min
Cook time: 10 min
Total time: 20 min
Yield: 4 servings
Cuisine: French
Ingredients: 4 Slices Rustic Bread (Sourdough or Brioche); 4 slices Ham (thick); 1,5 cup Gruyere Cheese (shredded); 2 tbsp Dijon Mustard; 1 tbsp Butter (unsalted); 1 tbsp Flour (all-purpose); 1 cup Milk; Salt & Pepper to taste; Pinch of fresh Nutmeg

A Classic Croque Monsieur is a traditional French grilled sandwich featuring ham, melted Gruyère cheese, and creamy béchamel sauce between toasted bread. It delivers restaurant-quality results in under 20 minutes with pantry staples.

🌍French

Total

20 min

Servings

4

Difficulty

Easy

Recipe Source

View original recipe

From Eatingeuropean · by Edyta

Ingredients

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9 Ingredients

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Instructions

1
Heat up your milk either in a saucepan or microwave but make sure it is not boiling.
2
In a frying pan, melt the butter. Once melted, add flour and whisk well. Start adding warm milk gradually until all milk is incorporated and the sauce is smooth and thick.
3
Season the sauce with salt, pepper, and nutmeg. Set aside.
4
Lightly toast your bread for a few minutes in a toaster oven. Once toasted spread mustard on one slice of the bread and add ham and cheese on the other slice. Put the slices together and repeat with the remaining bread.
5
Spread about 2 tablespoons of the béchamel sauce on top of each sandwich, add a little bit more shredded cheese, and place in the toaster oven for a few minutes until the cheese starts to melt.
6
Change the settings to broiler and broil the sandwich until the sauce is bubbly and golden (for about 30 seconds). Remove from the toaster and cut in half. Enjoy.

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Tips & Notes

Pro tips

Make béchamel first and let it cool slightly before spreading—hot sauce will wilt the bread and make assembly messy.
Shred cheese fresh rather than using pre-shredded; it melts more smoothly and evenly in the sandwich.
Butter the outside of the bread (not inside) for even browning and a crispy crust in the pan.
Medium heat is critical—too high burns the outside before cheese melts inside; aim for 3–4 minutes per side until golden and cheese begins leaking at edges.

Substitutions

Gruyère → Swiss or Emmental (similar texture and nuttiness)
Dijon mustard → whole-grain mustard (milder, less sharp)
Brioche/sourdough → challah or thick-cut white bread (adjust toasting time slightly)
Unsalted butter → salted butter (omit added salt in béchamel)

Storage & make-ahead

Leftover assembled sandwiches (uncooked) keep refrigerated for up to 2 hours; cooked Croque Monsieurs are best eaten immediately but can be wrapped and reheated gently in a low oven for 5 minutes.

Common Questions

Can I make a Croque Monsieur ahead of time?

Assemble the sandwich up to 2 hours before grilling and refrigerate. Cook immediately before serving for best results; assembled sandwiches won't toast evenly if left too long.