If you’re looking for a breakfast that feels like a warm hug on a plate, this Ham and Cheese Breakfast Casserole Recipe is exactly what you need. Combining the rich flavors of sweet caramelized onions, savory ham, and melty Gruyere cheese with soft challah bread soaked in an herby, custardy egg mixture, it creates a comforting, crowd-pleasing dish perfect for leisurely weekend mornings or special occasions. The balance of textures—from the tender baked bread to the creamy custard and crispy edges—makes every bite irresistible. Trust me, once you try this recipe, it might just become your new breakfast favorite.
Ingredients You’ll Need
This recipe brings together simple, pantry-friendly ingredients that each add their own magic to the casserole. From the silky softness of brioche bread to the fragrant thyme and the nutty notes of Gruyere, every element plays a key role in crafting a symphony of flavor and texture.
- 4 cups day-old challah or brioche bread: Using day-old bread helps absorb the egg mixture without becoming mushy, offering a perfect fluffy yet structured base.
- 2 tablespoons olive oil: Adds a subtle richness while sautéing the onions, giving a beautiful caramelized flavor.
- 1 tablespoon unsalted butter: Works alongside olive oil to enhance the sweetness and softness of the onions.
- 1 medium sweet yellow onion, diced: Brings a natural sweetness and depth to the casserole after slow caramelizing.
- ½ teaspoon Kosher salt: Essential for balancing and highlighting the flavors of all ingredients.
- ½ teaspoon freshly ground black pepper: Adds just the right amount of gentle heat and complexity.
- ¼ teaspoon granulated sugar: Helps the onions caramelize beautifully for that rich, golden color and sweet undertone.
- ½ lb thinly-sliced good deli ham, roughly cut: Provides hearty, savory goodness that pairs wonderfully with the cheese and herbs.
- 6 large eggs: The binding agent that creates the custardy texture every great breakfast casserole needs.
- 1½ cups milk or half and half: Adds creaminess to the egg base for extra indulgence.
- ½ teaspoon dry mustard: Brings a subtle tang and depth without overpowering the other flavors.
- ¼ teaspoon grated nutmeg: A tiny pinch gives the custard warmth and a hint of sweetness.
- 2 teaspoons fresh thyme leaves, minced: Fresh herbiness brightens the casserole and complements the ham perfectly.
- Salt & pepper to taste: Adjust to ensure every bite bursts with balanced seasoning.
- 1 cup shredded Gruyere or Swiss cheese: Melts into a luscious, savory layer that ties the entire dish together.
How to Make Ham and Cheese Breakfast Casserole Recipe
Step 1: Prepare Your Baking Dish
Start by spraying an 8-inch baking dish (about 1½ to 2 quarts) with non-stick cooking spray. This simple step ensures your casserole won’t stick and will come out easily after baking.
Step 2: Arrange the Bread Cubes
Cut your brioche or challah bread into 1-inch cubes and spread them evenly in the bottom of your baking dish. The bread serves as a soft, absorbent canvas for the custardy egg mixture and savory add-ins.
Step 3: 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 sugar. Cook slowly, stirring occasionally, until the onions turn a beautiful golden brown and smell irresistibly sweet—about 10 minutes. Patience here builds a deep, rich flavor base for the casserole.
Step 4: Whisk the Custard Mixture
In a medium bowl, whisk together the eggs, milk or half and half, dry mustard, nutmeg, fresh thyme, plus a pinch of salt and pepper. This egg mixture should be smooth and fragrant, ready to envelop every piece of bread and ham with creamy deliciousness.
Step 5: Layer Ham and Onions
Spread the roughly cut ham evenly over the bread cubes, then top with the caramelized onions. These layers bring the perfect savory, slightly sweet, and meaty contrast to the soft bread and custard.
Step 6: Add the Cheese and Pour the Egg Mixture
Sprinkle the shredded Gruyere or Swiss cheese over the onions, creating a luscious, melty layer. Then, pour the egg mixture gently over the entire dish, making sure the cheese and bread soak up all that custardy flavor.
Step 7: Press and Refrigerate Overnight
Press down gently on the casserole to ensure that all the bread cubes are soaked through. Cover the dish with foil or plastic wrap and refrigerate overnight. This step allows the flavors to meld beautifully and sets you up for an easy morning bake.
Step 8: Bake to Perfection
Take the casserole out of the fridge about 15 minutes before baking to let it come to room temperature. Preheat your oven to 350°F. Bake uncovered for 40 to 50 minutes, until the center is set, the edges are bubbly, and the top turns a gorgeous golden brown. If the casserole browns too quickly, simply cover it loosely with foil for the remaining time.
How to Serve Ham and Cheese Breakfast Casserole Recipe
Garnishes
A sprinkle of fresh thyme leaves or a handful of chopped chives on top right after baking adds a pop of color and fresh flavor to your casserole. If you’re feeling indulgent, a dollop of sour cream or a drizzle of hot sauce can also elevate this dish wonderfully.
Side Dishes
This casserole pairs beautifully with light, fresh sides like a crisp green salad with a lemon vinaigrette or a bowl of mixed fresh berries to balance the richness. For heartier breakfasts, add crispy breakfast potatoes or sautéed greens for texture and color.
Creative Ways to Present
For a brunch gathering, slice the casserole into neat squares and arrange them on a large platter. Garnish with sprigs of thyme and serve alongside small ramekins of mustard or jam for guests to customize their bites. You can even sprinkle some toasted nuts or seeds on top for a delightful crunch.
Make Ahead and Storage
Storing Leftovers
Your hearty ham and cheese casserole keeps beautifully in the refrigerator for up to 3 days. Store leftovers in an airtight container to maintain freshness and prevent drying out.
Freezing
This casserole freezes well if you want to make it ahead for busy mornings. Either freeze before baking (cover tightly with foil and plastic wrap) or freeze individual portions after baking. Just thaw overnight in the fridge before reheating.
Reheating
Reheat slices in a microwave or preheated oven at 350°F until warmed through. For the best texture, reheating covered in the oven will help keep the casserole moist while allowing the edges to crisp again.
FAQs
Can I use other types of bread?
Yes! While challah or brioche add a lovely richness, you can use any sturdy, slightly dense bread like French bread or Italian loaf. Just avoid super soft sandwich bread, as it might become too mushy.
What substitutions can I make for the cheese?
If Gruyere or Swiss aren’t available, mild cheddar, mozzarella, or even fontina are great alternatives that melt well and offer good flavor.
Can I add vegetables to this casserole?
Absolutely! Spinach, bell peppers, mushrooms, or even sun-dried tomatoes make excellent additions. Just sauté any veggies beforehand to remove moisture and boost flavor.
Is it necessary to refrigerate overnight?
While you can bake immediately, refrigerating overnight greatly improves the texture by allowing the bread to fully absorb the custard, resulting in a more cohesive and flavorful casserole.
How do I know when the casserole is done?
The casserole is baked when the edges are bubbly and golden brown, and a knife or toothpick inserted in the center comes out clean without wet custard.
Final Thoughts
I truly hope you give this Ham and Cheese Breakfast Casserole Recipe a try—it’s the kind of dish that brings people together around the table to start the day with smiles and full hearts. Whether it’s a weekend treat or a make-ahead breakfast, its warm, comforting flavors will keep you coming back for more. Happy cooking!
Print
Ham and Cheese Breakfast Casserole Recipe
- Prep Time: 20 minutes
- Cook Time: 40-50 minutes
- Total Time: overnight soaking plus 1 hour 10 minutes active
- Yield: 6 servings
- Category: Breakfast
- Method: Baking
- Cuisine: American
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
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.
