Recipe video above. A croque madame is basically the best grilled cheese sandwich you'll ever eat for brunch. I spent a lot of time testing different cooking methods, but the one I learned years ago from a French chef is truly the best. The trick is to grill both sides of the bread; otherwise, your sandwich ends up a little soggy. Also, I don't skimp on the bechamel. You can thank me for that later!
To make the béchamel, melt the butter in a small saucepan over medium heat. Add the flour and whisk for one minute. Slowly whisk in the milk then bring to a boil and cook until it thickens, for about 2 minutes. Season to taste with nutmeg and salt. Set aside to cool slightly while you prepare the sandwiches.
4 tablespoons butter, 2 tablespoons all-purpose flour, 1 ½ cups whole milk, Nutmeg and salt
Preheat your oven to low broil and position a rack near the top. (If your oven doesn't have a low broil option, move the rack down towards the middle.) Butter each slice of bread on one side and lay them buttered side down on a baking sheet.
8 slices bread, 4 tablespoons butter
To assemble the sandwiches, spread one teaspoon of mustard on four slices of bread. Spoon a heaping tablespoon of the sauce onto each of the eight slices. Lay two slices of ham and ½ cup of gruyere cheese on four slices and then top with the remaining slices of bread.
4 teaspoons dijon mustard, 8 thin slices of ham, 3 cups shredded gruyere
Heat a large skillet over medium heat. Add the sandwiches, working in batches if needed. Cook until the bottoms of the sandwiches are golden and then flip them over and cook until the second side is golden and the cheese is melty. Transfer them to the baking sheet.
Add a generous layer of bechamel sauce to the tops of each sandwich, using all of the sauce. Sprinkle each with ¼ cup of gruyere cheese, and then broil while you cook the eggs.
Add a little butter or oil to the pan and then crack the eggs into it. Season the eggs with salt and pepper and cook until the whites are set and the yolks are runny, about 2-3 minutes.
4 large eggs, Salt and pepper
Serve the sandwiches with an egg on top and a little minced parsley.
Minced parsley
Notes
Ham: It's best to get the ham from the deli so that you can ask for it thinly sliced. Packaged ham is cut too thick. If there is an option to get French ham, get that. Otherwise, get whichever type of ham looks the best. Mustard: I love the slightly tangy taste of mustard in this recipe, as it helps cut the richness. If you're not a fan of mustard, you can reduce the amount or omit it altogether. Make-Ahead: If you're making these for a party brunch, you may want to get a jump start on prepping them. You can make the bechamel and assemble the sandwiches a few hours in advance.