Save There's something about the way warm custard soaks into brioche that makes you feel like you're doing something slightly illicit in the kitchen. I was midway through making French toast on a lazy Sunday when I opened the fridge and saw blocks of good Gruyère staring back at me, and suddenly the whole dish pivoted. Instead of sweet, I went savory-rich, turning breakfast into something that tasted like someone's very sophisticated idea of comfort food. The first bite—that molten cheese meeting eggy bread meeting the salt and pepper in the custard—made me understand why some meals stick with you.
I made this for my sister's unexpected visit one autumn morning, and she sat at my kitchen counter with a cup of coffee, watching the sandwiches turn golden in the skillet. She kept saying the smell was all wrong for breakfast, and when I plated it with a small side salad, she laughed and said it looked like something a French bistro would charge way too much for. Two bites in, she stopped talking and just ate, which is the highest compliment anyone has ever paid my cooking.
Ingredients
- Eggs (3 large): These are your custard base, so fresh ones make a real difference in richness and flavor.
- Whole milk (3/4 cup): Don't skip this for a lighter option—the fat content creates the creamy coating that makes this special.
- Heavy cream (1/4 cup): This is what turns regular French toast into something luxurious and memorable.
- Granulated sugar (1 tbsp): Just enough to balance the salt and enhance the savory-sweet interplay.
- Kosher salt and black pepper (1/2 tsp each): The salt is essential here, not just a footnote—it brings out the cheese and custard flavors.
- Dijon mustard (1/2 tsp, optional but encouraged): A tiny bit adds a subtle edge that makes people wonder what they're tasting.
- Brioche or challah bread (8 slices, 1/2-inch thick): The bread matters tremendously because it needs to be sturdy enough to hold the custard without falling apart, yet soft enough to stay tender inside.
- Gruyère or sharp cheddar cheese (8 slices): Use good cheese here—it's the star alongside the custard, and grocery store singles will disappoint you.
- Unsalted butter (2 tbsp) and neutral oil (1 tbsp): The combination gives you the browning power of butter with the heat tolerance of oil.
Instructions
- Build your custard bath:
- Whisk the eggs, milk, cream, sugar, salt, pepper, and mustard until it's completely smooth with no streaks of egg white. This custard should smell subtly savory, not sweet—trust that it's going to be delicious even though it seems counterintuitive.
- Assemble the sandwiches:
- Lay out 4 slices of bread, top each with 2 slices of cheese, then cap with another slice of bread. The cheese should peek out just slightly at the edges, which is how you know you've got enough.
- Get your pan ready:
- Heat a large nonstick skillet over medium heat until a drop of water sizzles gently on contact. Add the butter and oil together, swirling them around—this matters because the oil helps the butter not burn while you're cooking multiple sandwiches.
- Dip with intention:
- Submerge each sandwich into the custard, one side first, letting it soak for maybe 2 seconds, then flip and do the other side. You want the bread thoroughly coated but not waterlogged, which is easier to judge than it sounds once you've done one.
- Cook to golden:
- Lay the sandwiches in the hot skillet and resist the urge to move them for 3 to 4 minutes—this is how they get that deep golden crust. Press gently with your spatula every minute or so, and listen for the sizzle to shift from aggressive to a gentle, satisfied hum. Flip, cook the other side for 3 to 4 minutes, and look for cheese starting to peek out from the edges.
- Rest and serve:
- Transfer the sandwiches to a cutting board for 2 minutes—this lets the inside set slightly so the cheese doesn't immediately ooze everywhere when you slice. Cut diagonally if you're feeling fancy, or straight down the middle if you're hungry.
Save That autumn morning turned into lunch, and my sister ended up staying through dinner just because she wanted to eat this again. It became the thing we make when we need to feel like we're conspiring on something delicious together, which is really what cooking with someone should be.
The Custard Matters More Than You'd Think
Most people approach custard like it's a vehicle for sweetness, but here it's the opposite—it's where savory lives. The mustard is subtle enough that no one will identify it, but it does something important to the flavor profile, making the cheese sing and the bread taste more interesting. If you're skeptical about putting mustard in something that's going to touch French toast, I understand, but try it anyway. The salt in the custard is what changes this from breakfast into something that could genuinely be served for dinner.
Variations That Actually Work
I've added thin spreads of fig jam between the cheese layers, and the sweetness against the savory custard creates this fascinating tension that shouldn't work but absolutely does. Caramelized onions do something similar—they add a soft sweetness and depth that makes you want another bite immediately. Once I tried Swiss cheese with a small handful of fresh thyme layered in, and it tasted like I'd made something accidentally sophisticated. The beautiful thing about this dish is that it's flexible enough to take your instincts seriously.
Building Your Plate Around This
Serve this with something green and acidic to cut through the richness—a simple arugula salad with lemon vinaigrette works perfectly, or a bowl of tomato soup if you're going full comfort mode. The cheese is generous, the custard is rich, so you want something bright on the side to keep the whole experience from feeling heavy. I've also served it with a small green salad and a poached egg on top when I was feeling ambitious, though honestly the sandwich is sufficient all on its own.
- A crisp green salad with vinaigrette is the easiest companion and worth it.
- Tomato soup transforms this into the kind of meal you remember for years.
- Trust your instincts with cheese varieties because good cheese makes all the difference.
Save This dish became the thing I make when I want to tell someone I care about them through food, which might sound dramatic until you've actually made it and tasted how good it is. It's the kind of meal that makes ordinary moments feel special.
Recipe Guide
- → What type of bread works best?
Brioche or challah are ideal for their rich texture and ability to hold custard without sogging.
- → Which cheeses complement this dish?
Gruyère or sharp cheddar offer a great melt and sharp flavor, but Swiss or fontina can also be used.
- → How do I prevent the bread from becoming too soggy?
Dip briefly in custard, ensuring both sides are coated but not soaked through, then cook promptly.
- → Can I prepare these sandwiches ahead of time?
Yes, assemble and refrigerate the sandwiches, then dip and cook just before serving for best results.
- → What cooking fat is recommended?
A combination of unsalted butter and neutral oil creates a rich flavor and helps prevent burning during pan-searing.