What's the difference between a Croque Monsieur and Croque Madame?

A Croque Monsieur is a ham and cheese sandwich without an egg; a Croque Madame is topped with a fried egg, earning its feminine title.

Can I make the Mornay sauce ahead of time?

Yes, make it up to 2 days ahead and refrigerate. Reheat gently over low heat, stirring often, and thin with a splash of cream if it's too thick.

Should the egg yolk be runny?

Yes—the runny yolk is essential. Cook the egg over medium heat until the whites are set but the yolk still jiggles slightly, then slide it onto the sandwich.

What cheese works best if I can't find Havarti or Muenster?

Swiss, Gruyère, or Emmental are good substitutes; they melt smoothly and won't overpower the ham. Avoid low-moisture cheeses like aged cheddar.

Can I broil instead of pan-frying the sandwich?

Yes—assemble on a baking sheet, top with Mornay, and broil 4–5 inches from heat for 3–4 minutes until bubbly. Add the fried egg after broiling.

Croque Madame with Mornay Sauce

Name: Croque Madame with Mornay Sauce
Prep time: 10 min
Cook time: 10 min
Total time: 20 min
Yield: 4 servings
Cuisine: French
Ingredients: 8 slices thick-cut white bread; 2 tbsp unsalted butter; 2 tbsp all-purpose flour; 1.5 cups heavy cream; 1/2 cup grated Parmesan cheese; 4 tbsp Dijon mustard; 1 lb sliced ham; 8 slices Havarti cheese; 8 slices Muenster cheese; 8 large eggs; 1 tbsp butter, for frying eggs; salt, to taste; black pepper, to taste; 2 tbsp fresh chives, chopped

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Croque Madame with Mornay Sauce | CookOS

Ingredients

8 slices thick-cut white bread
2 tbsp unsalted butter
2 tbsp all-purpose flour
1.5 cups heavy cream
1/2 cup grated Parmesan cheese
4 tbsp Dijon mustard
1 lb sliced ham
8 slices Havarti cheese
8 slices Muenster cheese
8 large eggs
1 tbsp butter, for frying eggs
salt, to taste
black pepper, to taste
2 tbsp fresh chives, choppedoptional

14 Ingredients

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Instructions

1
Preheat your oven to 350°F (175°C).
2
Toast the slices of bread in a large pan over medium heat until golden brown on both sides. Set aside on two baking sheets.
3
To make the Mornay sauce, melt 2 tbsp of butter in a pan over medium heat. Whisk in the flour to create a roux and cook for about 1 minute.
4
Slowly pour in the heavy cream while whisking continuously to avoid lumps. Bring to a simmer.
5
Season the sauce with salt and black pepper. Stir in the grated Parmesan cheese until the sauce is smooth and fully melted.
6
To assemble the sandwiches, lay out four slices of toasted bread on the baking sheets. Spread a layer of Dijon mustard on each.
7
Layer each sandwich with sliced ham, Havarti cheese, another layer of ham, and Muenster cheese.
8
Place the remaining slices of toasted bread on top of each sandwich.
9
Generously spoon the Mornay sauce over the top of each sandwich, spreading it to cover the surface.
10
Place the baking sheets in the preheated oven and bake for 5-7 minutes, or until the sauce is bubbly and the cheese is melted.
11
While the sandwiches are baking, fry the eggs. Melt 1 tbsp of butter in a large non-stick pan over medium heat. Crack the eggs into the pan.
12
Season the eggs with salt and pepper and cook to your desired doneness, keeping the yolks runny for a classic Croque Madame.
13
Remove the sandwiches from the oven. Carefully place two fried eggs on top of each sandwich.
14
Garnish with freshly chopped chives and serve immediately.