Description
This Ham and Cheese Breakfast Casserole is a savory and satisfying make-ahead dish perfect for any morning meal. Featuring tender cubes of challah or brioche bread soaked in a flavorful mixture of eggs, milk, herbs, and topped with savory ham and melted Gruyere or Swiss cheese, this casserole is easy to prepare and perfect for feeding a crowd. With a rich blend of caramelized onions and fresh thyme, it delivers a comforting, gourmet breakfast experience.
Ingredients
Scale
Bread and Base
- 4 cups day-old challah or brioche bread, cut into 1-inch cubes
- 2 tablespoons olive oil
- 1 tablespoon unsalted butter
Vegetables and Seasonings
- 1 medium sweet yellow onion, peeled and diced
- ½ teaspoon kosher salt
- ½ teaspoon freshly ground black pepper
- ¼ teaspoon granulated sugar
- salt & pepper to taste
- 2 teaspoons fresh thyme leaves, minced
- ½ teaspoon dry mustard
- ¼ teaspoon grated nutmeg
Protein and Dairy
- ½ lb. thinly sliced good deli ham, roughly cut
- 6 large eggs
- 1½ cups milk or half and half
- 1 cup shredded Gruyere or Swiss cheese
Instructions
- Prepare the baking dish: Spray an 8-inch baking dish (1½-2 qt) with non-stick cooking spray to prevent sticking during baking.
- Arrange the bread cubes: Cut the brioche bread into 1-inch cubes and spread them evenly in the bottom of the prepared baking dish.
- Caramelize the onions: Heat olive oil and butter in a large skillet over medium-low heat. Add the diced onion, kosher salt, black pepper, and granulated sugar. Sauté gently until the onions are lightly caramelized and fragrant, approximately 10 minutes, stirring occasionally to avoid burning.
- Mix the custard: In a medium bowl, whisk together the eggs, milk or half and half, dry mustard, grated nutmeg, minced thyme, and salt and pepper to taste. Ensure the mixture is smooth and well combined.
- Layer the casserole: Spread the roughly cut ham evenly over the bread cubes in the baking dish, then spread the caramelized onion mixture on top of the ham.
- Add cheese and pour custard: Sprinkle the shredded Gruyere or Swiss cheese evenly over the onion layer, then pour the egg mixture over the entire casserole.
- Soak and refrigerate: Press down gently on the top to ensure all bread cubes are saturated with the egg mixture. Cover the dish tightly and refrigerate overnight to allow flavors to meld and the bread to soak fully.
- Bring to room temperature and preheat oven: Remove the casserole from the refrigerator 15 minutes before baking to warm slightly on the counter. Meanwhile, preheat the oven to 350°F (175°C).
- Bake the casserole: Bake the uncovered casserole for 40-50 minutes, or until the center is set, edges are bubbly, and the top begins to brown. Test doneness by inserting a knife in the center—it should come out clean.
- Manage browning if needed and serve: If the casserole browns too quickly before fully cooking, loosely cover the top with foil to prevent over-browning. Serve warm for breakfast, brunch, or any meal and enjoy!
Notes
- Using day-old challah or brioche bread helps ensure the bread soaks up the egg custard without becoming too mushy.
- You can substitute Swiss cheese for Gruyere if preferred or use a combination of both for richer flavor.
- Refrigerating overnight is essential for best texture and flavor melding but if short on time, allow at least 1 hour of soaking before baking.
- This casserole can be made ahead and reheated gently in the oven for convenient meal prep.
- Adjust salt and pepper seasoning to taste before baking, especially if using salty ham.
