Croque Madame Recipe

Prepare bread and assemble

Preheat oven to 425°F (220°C). Lightly butter one side of each bread slice. On the unbuttered side of four slices, spread about 1/2 tsp Dijon mustard each. Layer 2 slices ham on each mustard-spread slice, then distribute Brie slices evenly (about 2 oz per sandwich). Sprinkle about 2 tablespoons grated Swiss cheese on top of the Brie and scatter 2 basil leaves (chiffonade) over the cheese. Top each with the remaining bread slice, buttered side up.

Toast briefly

Place the assembled sandwiches on a baking sheet. Bake for 5–7 minutes just to warm and meld cheeses; you want the sandwiches warmed through before adding sauce but not deeply browned yet.

While sandwiches warm, make the béchamel. In a small saucepan over medium heat, melt 2 tablespoons butter. Add 2 tablespoons flour and whisk constantly for 1–2 minutes to cook the raw flour taste, forming a blond roux.

Gradually whisk in 1 cup warm milk a little at a time to avoid lumps. Continue whisking until smooth and thickened, 3–4 minutes. Reduce heat to low and stir in the pinch of nutmeg, 1 tsp salt, 1 tsp pepper, and the 2 tbsp grated Parmesan if using. Taste and adjust seasoning; sauce should be creamy and pourable but not runny. Keep warm.

Stir in 1/4 cup of the grated Swiss cheese into the béchamel to add cheesiness (reserve remaining Swiss for topping). This helps the sauce cling to the sandwiches.

Remove the lightly toasted sandwiches from the oven. Spoon a generous tablespoon of béchamel over the top of each sandwich, then sprinkle the remaining grated Swiss cheese evenly across all four sandwiches (about 2–3 tablespoons each).

Return the baking sheet to the oven and bake at 425°F (220°C) for 6–8 minutes, or until the cheese topping is bubbling and beginning to brown.

If you want a deeply browned gratin finish, switch the oven to broil for 1–2 minutes—watch closely to avoid burning.

While sandwiches finish baking, fry the eggs. Heat 1 tablespoon olive oil or butter in a nonstick skillet over medium heat. Crack eggs into the skillet and cook until whites are set but yolks remain runny, about 2–3 minutes for sunny-side up. For over-easy, flip gently and cook 15–30 seconds more. Season each egg with a pinch of salt (about 1/8 tsp per egg) and a grind of black pepper.

When the sandwiches are done, remove from oven and place each on a plate. Carefully top each Croque with a fried egg. Garnish with extra basil leaves if desired and serve immediately.