# What You Need:
→ 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 mix
→ For Cooking
10 - 2 tablespoons unsalted butter
11 - 1 tablespoon neutral oil such as canola
# Directions:
01 - Whisk together eggs, whole milk, heavy cream, granulated sugar, kosher salt, black pepper, and optional Dijon mustard in a shallow bowl until smooth and fully combined.
02 - Lay 4 slices of bread on a flat surface. Layer each with 2 slices of cheese, then top with 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 evenly coat the surface.
04 - Carefully immerse each sandwich in custard mixture, coating both sides thoroughly without allowing the bread to become overly saturated.
05 - Place custard-coated sandwiches onto the skillet. Cook for 3 to 4 minutes per side, pressing gently with a spatula until golden brown and cheese is fully melted. Repeat in batches, replenishing butter and oil as needed.
06 - Transfer cooked sandwiches to a cutting board. Allow resting for 2 minutes before slicing and serving warm.