Croque Monsieur Breakfast Casserole

01Method

1. 1

   Grease a 9x13-inch baking dish with butter. Spread half the bread cubes across the bottom, then scatter half the ham and about three-quarters of a cup of Gruyère on top. Repeat the layers with the remaining bread, ham, and another three-quarters of a cup of Gruyère. Mix the parmesan with the reserved Gruyère, seal in a container, and refrigerate for use as a topping later.

2. 2

   Whisk together the eggs, milk, cream, Dijon mustard, salt, pepper, and nutmeg (if using) in a large bowl until fully combined. Pour the custard evenly over the layered casserole, gently pressing the bread down so it soaks up the liquid. Cover the dish tightly and chill for at least 2 hours or overnight.

3. 3

   When ready to cook, heat the oven to 350°F. Remove the cover, then distribute the reserved cheese mixture evenly across the surface. Bake for 45 to 50 minutes until the casserole is puffed, golden on top, and firm in the center. If the surface darkens too fast, loosely cover with foil for the final 10 minutes.

4. 4

   Allow the casserole to rest for 10 minutes before cutting into portions. Serve warm. Leftovers keep in the refrigerator for up to 3 days; reheat in a 350°F oven for 15 to 20 minutes, or warm individual servings in the microwave.