Croque Monsieur

Croque Monsieur

The iconic French bistro sandwich: toasted pain de mie layered with Paris ham, a quick béchamel, and nutty Gruyère, gratinéed until bubbling. Crown with a fried egg to make it a Croque Madame.

Prep

15 min

Cook

15 min

Total

30 min

Serves

2

Difficulty

Easy

Recipe ingredients

• •60 g (4 tbsp) unsalted butter, softened, divided
• •30 g (¼ cup) all-purpose flour
• •250 ml (1 cup) whole milk, warm
• •1 pinch freshly grated nutmeg
• •40 g (1½ oz) Gruyère, coarsely grated, for the béchamel
• •4 slices pain de mie or soft white sandwich bread, crusts on; a thin Pullman loaf is traditional
• •10 g (2 tsp) Dijon mustard
• •120 g (4 oz) Paris-style cooked ham, Jambon de Paris or other thinly sliced, mild cooked ham
• •80 g (3 oz) Gruyère, finely grated, for topping
• •0.5 tsp (½ tsp) lemon juice, added to the béchamel to keep it pale and bright
• •2 whole eggs, optional, for Croque Madame

Steps

1. 1 Make the béchamel: melt 30 g (2 tbsp) of the butter in a small saucepan over medium heat. Whisk in the flour and cook, whisking constantly, 60–90 seconds until pale and foamy — do not let it brown.
2. 2 Off the heat, whisk in the warm milk a little at a time, returning to the heat between additions, until you have a smooth, thick sauce that coats the back of a spoon, about 3–4 minutes.
3. 3 Season with salt, white pepper, the nutmeg, and lemon juice. Off the heat, whisk in the 40 g grated Gruyère until melted. Cover the surface with plastic wrap directly on the sauce to prevent a skin; keep warm.
4. 4 Heat the oven to 220 °C / 425 °F (fan 200 °C / 400 °F). Lightly butter one side of each bread slice with about half the remaining softened butter.
5. 5 Toast the buttered sides in a large skillet over medium heat, 1–2 minutes per side, until pale gold. (A traditional alternative is to leave the bread soft and bake the whole sandwich longer.)
6. 6 Spread the untoasted side of two slices with Dijon mustard, then a thin, even layer of béchamel, followed by the ham folded loosely and another spoonful of béchamel. Top with the remaining bread, toasted side up.
7. 7 Spoon or spread the remaining béchamel over the tops of the sandwiches, then blanket with the 80 g grated Gruyère, pressing it on so it adheres.
8. 8 Place on a parchment-lined tray and bake 8–10 minutes, then switch to the broiler / grill 2–3 minutes at 230 °C / 450 °F until the cheese is deeply golden, bubbling, and slightly spotted — watch closely so it does not scorch.
9. 9 For a Croque Madame, while the sandwiches bake, fry the eggs sunny-side up in a little butter over medium-low heat until the whites are fully set and the yolks remain runny, 2–3 minutes. Season with salt and pepper.
10. 10 Slide each sandwich onto a warmed plate, top with a fried egg, and serve immediately, ideally with a simple green salad.