Ham Katsu Croque Madame

Let's take a French classic and it give it an Asian twist! Ham katsu croque madame takes the best of both worlds to create an incredible breakfast sandwich. Filled with crispy ham katsu and topped with creamy mornay sauce, this is the brunch dish we all need!

Watch how to make this

Ingredients

• Gruyere: Gruyere cheese is essential for its rich, nutty flavor and excellent melting properties. It contributes a creamy texture to the Mornay sauce and enhances the overall taste of the sandwich. 
• Japanese mustard: Adds a subtle tanginess and depth of flavor to the Mornay sauce. Its unique taste helps cut through the richness of the cheese and ham. If you can't find Japanese mustard, you can substitute it with Dijon mustard.
• Black forest ham: Provides a smoky, savory flavor that is integral to the sandwich. Use high quality ham for the best results.
• Panko: Panko breadcrumbs are used for breading the ham katsu, providing a light, crispy texture when fried.
• Milk bread: Milk bread is chosen for its soft, fluffy texture and slight sweetness, which enhances the overall flavor of the sandwich. Its ability to hold up against moist ingredients like Mornay sauce while still being tender makes it ideal for this dish. If you can't find milk bread, you can use regular white bread, French loaf, or sourdough.

Substitutions and variations

• Protein: Experiment with other meats such as prosciutto or turkey for a lighter substitute.
• Gluten-free: Use your favorite gluten-free white bread and substitute flour with gluten-free all-purpose flour.

Step-by-step instructions

Step 1: Make mornay sauce

Let's begin by preparing the Mornay sauce. This sauce is essentially a cheese sauce. Ever made mac and cheese? Well, the idea is the same but we're using gruyere instead of cheddar and adding special ingredients like Japanese mustard and nutmeg.

Melt butter in a medium saucepan over medium heat, then whisk in flour to create a roux. Gradually add milk, whisking constantly to prevent lumps from forming. Bring the mixture to a simmer, stirring frequently until it thickens.

Remove the sauce from heat and stir in grated Gruyere cheese, Japanese mustard, and a pinch of nutmeg until the cheese is fully melted. Season with salt to taste and set aside. Feel free to make the sauce up to 3 days in advance.

The sauce does thicken as it cools. If preparing the sauce ahead of time, add a splash of milk to help loosen it up.

Step 2: Prepare ham katsu

Next, prepare the ham katsu by setting up a breading station with three shallow bowls: one with flour, one with beaten eggs, and one with panko breadcrumbs. Stack two slices of Black Forest ham together, then dredge in flour, dip in egg, and coat thoroughly with panko.

Repeat with the remaining ham slices. At this point, you can chill the breaded ham slices until you're ready to fry.

Heat oil in a large skillet to a depth of about 1 inch, until it reaches 340°F. We're going to shallow fry the ham but you can also deep fry it if you prefer.

Carefully place the breaded ham into the hot oil and fry until golden brown on both sides, about 2-3 minutes per side. Drain on paper towels to remove excess oil.

Step 3: Assemble sandwiches

Now that all of the components are done, let's assemble the sandwiches. To add that special Japanese touch, we're using milk bread as the base. Milk bread has wonderfully soft texture but is still sturdy enough to hold the weight of the sauce. You can also use sourdough, French loaf, or regular white bread.

If you're staying true to Japanese form, you can also remove the crusts from the bread. However, I liked the crispy edges so I chose to keep them on.

To assemble the sandwiches, butter one side of each slice of milk bread. Place four slices butter-side down and top with the fried ham katsu and grated Gruyere. Cover with the remaining bread slices, butter-side up.

Then, heat a large non-stick skillet over medium heat and cook the sandwiches until golden brown on both sides, about 2-3 minutes per side. This step is basically like making grilled cheese so if you've made grilled cheese before, you're already a pro at this step!

Now the final step. Preheat your broiler to high and place the cooked sandwiches on a baking sheet. Spread about ¼ cup of Mornay sauce over the tops of each, spreading it evenly. Broil the ham katsu croque madame for about 2 minutes, or until the sauce is bubbly and has seeped into the bread.

While the sandwiches are broiling, fry your eggs. For perfectly fried eggs, heat a non-stick skillet over medium heat with a small amount of butter or oil. Crack the eggs into the pan and cook until the whites are set but the yolks are still runny, about 2-3 minutes. For over-easy eggs, carefully flip and cook for an additional 30 seconds.

Top each sandwich with a fried egg, sprinkle with chopped chives, and if desired, add a pinch of togarashi for an extra kick of flavor. Serve immediately while the sandwich is still warm and the egg yolk is runny, allowing it to create a rich sauce when broken.

One bite into that perfectly cooked egg mixed with that rich sauce with the crispy ham and I was in heaven. I was immediately taken back to when I was at Camelia, enjoying every bite of this indulgent sandwich. Even without a fried egg, this sandwich is incredible. In fact, I would consider it a must-try!

Make-ahead and storage tips

• Make-ahead: You can prepare the mornay sauce up to 3 days in advance. You can also bread the ham ahead of time and fry just before assembling the sandwiches.
• Store: Store in an airtight container in the fridge for up to 5 days without the fried egg. Reheat in the oven at 300 degrees F for 10-15 minutes or until warmed through.

Frequently asked questions

More breakfast sandwich recipes

Looking for more breakfast sandwich ideas? Try these:

Recipe

Print Recipe

Ham Katsu Croque Madame

Total Time1 hour hr

Course: Breakfast, Main Course

Cuisine: French, Japanese

Keyword: sandwich

Servings: 4

Author: Christine Ma

Ingredients

Mornay sauce:

• 2 tablespoons butter
• 2 tablespoons all-purpose flour
• 1 ¼ cup milk
• ½ cup shredded gruyere cheese
• 1 teaspoon Japanese mustard
• pinch of nutmeg
• salt

Ham katsu:

• 8 slices black forest ham
• ¼ cup all-purpose flour
• 2 large eggs beaten
• 1 cup panko
• oil for frying

Remaining ingredients

• 8 slices milk bread
• 6 ounces grated gruyere cheese
• ¼ cup butter softened at room temperature
• 4 fried eggs
• 2 tablespoons chopped chives
• togarashi for serving optional

Instructions

• Make mornay sauce. Melt butter in a medium sauce pot over medium heat. Add flour, whisking to combine. Slowly add the milk, whisking constantly. Bring to a simmer and cook until thickened, stirring frequently. Remove the sauce from heat and stir in gruyere, mustard, and nutmeg, mixing until cheese has melted. Season with salt and set aside.
• Prepare ham katsu. Place flour in a shallow bowl, eggs in another bowl, and panko in a third bowl. Stack two slices of ham and dredge in flour, shaking off the excess. Dip the ham in eggs, and coat in panko, making sure to evenly coat all sides. Repeat with remaining ham.
• Add enough oil in a large saute pan to come up 1-inch up the sides. Heat over medium-high heat until the temperature reaches 340 degrees F. Carefully lay the breaded ham in the oil and fry until golden brown. You may have to cook the ham in batches. Remove ham from the oil and place on paper towels to drain excess oil.
• Assemble sandwiches. Spread butter on each of the bread slices. Flip half of the slices over so that the buttered side is facing down. Top with ham katsu and grated gruyere. Place the remaining bread on top, with the buttered side facing up.
• Heat a large nonstick saute pan over medium heat. Lay the sandwiches and cook until golden brown, about 2 minutes. Flip and cook until golden brown on the other side. Remove from heat.
• Preheat broiler to high.
• Lay sandwiches on a baking sheet and spread about ¼ cup mornay sauce on top. Broil until the sauce bubbly and has seeped into the bread, about 2 minutes.
• Meanwhile, fry the eggs until desired degree of doneness. Top the sandwiches with fried eggs, chopped chives, and a sprinkle of togarashi. Serve immediately.

Notes

You can prepare the mornay sauce up to 3 days in advance.