# Components:
→ Custard Mixture
01 - 3 large eggs
02 - 3/4 cup whole milk
03 - 1/4 cup heavy cream
04 - 1 tablespoon granulated sugar
05 - 1/2 teaspoon kosher salt
06 - 1/2 teaspoon ground black pepper
07 - 1/2 teaspoon Dijon mustard (optional)
→ Bread
08 - 8 slices brioche or challah bread, about 1/2-inch thick
→ Cheese Filling
09 - 8 slices Gruyère or sharp cheddar cheese, or a combination
→ For Cooking
10 - 2 tablespoons unsalted butter
11 - 1 tablespoon neutral oil, such as canola
# Preparation Steps:
01 - In a shallow bowl, whisk together eggs, whole milk, heavy cream, sugar, kosher salt, black pepper, and optional Dijon mustard until well combined.
02 - Lay 4 slices of bread on a clean surface and top each with 2 cheese slices. Cover with the remaining bread slices to form sandwiches.
03 - Warm a large nonstick skillet or griddle over medium heat. Add 1 tablespoon butter and 1/2 tablespoon oil, swirling to coat evenly.
04 - Briefly soak each sandwich in the custard mixture, coating both sides thoroughly without saturating the bread.
05 - Place custard-coated sandwiches in the skillet. Cook each side for 3 to 4 minutes, pressing gently, until golden brown and cheese is melted. Repeat in batches as needed, replenishing butter and oil.
06 - Transfer sandwiches to a cutting board and let rest for 2 minutes before slicing and serving warm.