A cafe mainstay, this hot satisfying inexpensive grilled ham sandwich comes with an egg or without (the Croque Monsieur). Croquer means to crunch.

Here’s a recipe:

5 tablespoons unsalted butter
3 tablespoons all-purpose flour
2 cups whole milk
1/4 teaspoon salt
1/8 teaspoon black pepper
1/8 teaspoon freshly grated nutmeg
3 1/2 ounces coarsely grated Gruyère cheese (1 1/3 cups)
8 slices firm white sandwich bread
4 teaspoons Dijon mustard
1/2 pound thinly sliced cooked ham
4 eggs

The sauce:
Melt 3 tablespoons butter in a heavy saucepan over moderately low heat, then whisk in flour and cook 1 minute. Add milk and continue stirring until thick. Add salt, pepper, nutmeg, and 1/3 cup cheese.

Make sandwiches:
Spread 1 1/2 tablespoons sauce evenly over each of 4 slices of bread, then sprinkle evenly with remaining cheese (1/4 cup per slice). Spread mustard evenly on remaining 4 bread slices and top with ham, dividing it evenly, then invert onto cheese-topped bread to form sandwiches.

Melt 1 tablespoon butter in a 12-inch nonstick skillet over moderately low heat, then cook sandwiches, turning over once, until golden. Remove from heat and transfer sandwiches to baking pan.

Top each sandwich with 1/3 cup sauce, spreading evenly. Broil sandwiches 4 to 5 inches from heat until sauce is bubbling and golden.

For the Madame, top each sandwich with a fried or poached egg and serve immediately.

Some places where this classic dish is served:

Café de la Comédie
57 rue St Honoré 75001
metro: Palais Royal/Musée du Louvre

Café de Flore
172 Boulevard Saint-Germain 75006

Café La Source
49 bd de la Tour Maubourg 75007
metro: Invalides

Café La Belle Férronnière
53 Rue Pierre Charron, 75008

La Place Royale
2bis Place des Vosges 75004

Le Village Monge
96 rue Monge 75005
metro: Jardin des Plantes/Austerlitz

Le Vélocipèd
79 bd Sébastopol 75002
metro: Arts & Métiers/Rambuteau

Price: 6 to 10 euros, depending on the establishment. Bon appetite!