The Croque Madame sandwich is essentially a ham and cheese sandwich with an egg on top. A Croque Monsieur does not have an egg. What they both have that sets them apart from an ordinary ham sandwich, is a rich béchamel Sauce. Put all that on crusty sourdough bread, and the result is no ordinary ham sandwich. If you make extra béchamel sauce, here are seven ideas from Spruce Eats for how to use it!
You can make this Croque Madame sandwich with a fried egg, which is traditional, or a poached egg, my favorite way! If you choose to use poached eggs, please try my recipe for Perfectly Poached Eggs!
For the béchamel sauce:
- 6 ounces salted butter, divided
- 2 TBS flour
- 1 cup whole milk
- 1 bay leaf
- ½ tsp kosher salt ((plus more for seasoning))
- ¼ cup grated parmesan cheese
- ¼ tsp crushed red pepper flakes (optional)
- ¼ tsp white pepper (optional)
For the sandwich:
- 8 slices sourdough bread, sliced thick
- ½ lb sliced ham ((use good quality ham for this))
- 12 oz Gruyere cheese, grated and divided
- 4 eggs
For the béchamel Sauce:
- In a small saucepan, melt 1 ounce (2 TBS) butter over low heat.
- Whisk in the flour and cook, stirring constantly, for 2 to 3 minutes. Do not allow it to brown!
- Warm the milk in a separate pan and add it to the roux (butter and flour combination). Add the bay leaf, red pepper flakes, and white pepper. Cook, stirring frequently, until the mixture thickens, about 8-10 minutes, on low heat.
- Remove and discard the bay leaf. Remove from heat and stir in the Parmesan cheese. Set pan aside to allow the sauce to cool.
For the sandwich:
- Arrange 4 slices of the sourdough bread on a flat surface. Top each with 2 to 3 slices of ham. I like to warm it up a bit first, but totally optional.Mix together half of the Gruyere cheese and the béchamel sauce. Taste for seasoning. Spread a little of the sauce on top of the ham and top each with another slice of bread.
- Mix together half of the grated Gruyere cheese and the bechamel sauce. Taste for seasoning and add additional salt or white pepper if desired.
- Spread a little of the sauce on top of the ham and top each with another slice of bread.
- Heat a large cast iron skillet over medium heat. Add half of the remaining butter (2 TBS) and melt. Place 2 of the sandwiches in the skillet and brown on one side, about 2 minutes. Turn on the other side and brown 2 more minutes. Transfer sandwich to a baking sheet. Repeat with the remaining butter and sandwiches. Spread the remaining béchamel on top of the sandwiches and top with the other half of the Gruyere cheese.
- Spread the remaining béchamel on top of the sandwiches and top with the other half of the Gruyere cheese. Sprinkle on a little more Parmesan if desired.
- You can choose to top your sandwich with a fried egg or a poached egg. If frying the eggs, you can cook them in the same skillet with a little additional butter. Yolks should be runny but whites completely cooked. You can also make poached eggs in a sauce pan if preferred. While the eggs are frying or poaching, place the sandwiches under the broiler. Broil until the top becomes golden brown, 1 to 2 minutes. Watch closely! Season the eggs with salt and top each sandwich with an egg. Serve immediately.