Christmas Breakfast Casserole: Hearty, Easy Morning Bake

Ingredients for Your Christmas Breakfast Casserole

• Stale Bread: You need this for structure, hon! Don’t use fresh, soft bread unless you want mush. I swear by day-old sourdough, it just holds up so well and gives it a lovely tang. I tried fresh white bread once, and it just dissolved, a total mess.
• Breakfast Sausage: Get a good quality one, please. It really makes a difference. The savory goodness is key. I’ve tried turkey sausage, and it worked, kinda, but the pork just has that richness. No judgment if you prefer turkey, though!

• Eggs: The binder! Use large eggs, and don’t skimp. I usually add an extra one or two because, well, more eggy goodness. Fresh is always best, I can tell the difference in the fluffiness.

• Milk: Whole milk, no questions asked. Don’t use skim milk, just don’t. The fat content is crucial for that rich, creamy texture. I once used 2% and it was… fine, but not the same luxurious feel.

• Cheddar Cheese: Sharp cheddar, grated yourself! Pre-shredded has weird anti-caking stuff that changes the melt. The tang of sharp cheddar really cuts through the richness, it’s a must.

• Onion & Bell Pepper: A humble duo, but they add so much flavor and a little bit of crunch. I usually dice them pretty small, because nobody wants a huge chunk of raw onion in their breakfast, right?
• Dijon Mustard: A secret weapon! Just a teaspoon adds a subtle tang that brightens everything. You won’t taste “mustard,” I promise, just a little something extra.
• Salt & Black Pepper: Season generously! This dish needs it. I always taste a tiny bit of the egg mixture before adding the bread, just to make sure it’s seasoned right.

Instructions for Your Christmas Breakfast Casserole

Prep the Bread & Sausage:

First things first, grab that stale bread and tear it into bite-sized pieces, about 1-inch cubes. Don’t be shy, just rip it up! Then, in a large skillet, brown your breakfast sausage over medium heat, breaking it up as it cooks. I love the smell of the sausage sizzling, it just signals that something good is coming. Drain off any excess grease, nobody wants a greasy casserole, trust me, I’ve made that mistake before and it was a bit much.

Sauté the Veggies:

Once the sausage is cooked, toss in your diced onion and bell pepper into the same skillet with a tiny bit of the sausage fat left behind. Sauté them until they’re softened and a bit translucent, about 5-7 minutes. This step is important for developing flavor, don’t rush it! I sometimes get impatient here, but cooking them down really makes a difference in the final texture of the Christmas Breakfast Casserole. This is where the kitchen starts smelling amazing, honestly.

Assemble the Christmas Breakfast Casserole Base:

Now for the fun part! In a large bowl, whisk together the eggs, milk, Dijon mustard, salt, and black pepper until everything is well combined and a bit frothy. This is where you can really see the magic happening. Stir in about half of your grated cheddar cheese, the cooked sausage, and the sautéed veggies. Then, gently fold in the bread cubes, making sure every piece gets coated in that lovely eggy mixture. Don’t overmix, though, or your bread might get too soggy!

Let it Soak Overnight:

Transfer the entire mixture to a greased 9×13 inch baking dish. Press it down gently to ensure everything is submerged. Cover the dish tightly with plastic wrap and pop it into the fridge overnight, or for at least 4 hours. This soaking time is crucial, it allows the bread to really absorb all those flavors. I once tried to bake it right away, and it just wasn’t the same, the bread was still a bit dry. Patience is a virtue here, my friend, especially for a truly great Christmas Breakfast Casserole.

Bake Your Christmas Breakfast Casserole:

When you’re ready to bake, pull the casserole out of the fridge about 30 minutes before baking to let it come closer to room temperature. Preheat your oven to 375°F (190°C). Uncover the dish, sprinkle the remaining cheddar cheese over the top. This is where it starts to look really appealing, all that cheesy goodness! Bake for 45-55 minutes, or until the casserole is golden brown and puffed up, and a knife inserted into the center comes out clean. If it’s browning too quickly, loosely tent it with foil.

Rest & Serve:

Once it’s beautifully golden and bubbly, take the Christmas Breakfast Casserole out of the oven and let it rest for about 10-15 minutes before serving. This resting period allows the casserole to set up properly, making it easier to slice and serve. Trust me, waiting is the hardest part, but it’s worth it! The smells filling your kitchen will be incredible, a truly festive aroma. Slice into squares and serve warm. Enjoy that delicious, hearty bite!

Storage Tips for Your Christmas Breakfast Casserole

This Christmas Breakfast Casserole is a superstar for leftovers, honestly! Once it’s completely cooled, cover it tightly with plastic wrap or transfer individual portions to airtight containers. It’ll keep beautifully in the fridge for up to 3-4 days. I’ve reheated slices in the microwave (gently, please, don’t blast it or the eggs can get rubbery I microwaved it once too high and it was a bit sad lol) or, even better, in the oven at 300°F (150°C) until warmed through. The oven method really helps the edges crisp up again. You can even freeze individual portions for up to a month! Just thaw overnight in the fridge before reheating. It holds up surprisingly well, though the texture might be slightly softer after freezing.

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Ingredient Substitutions for Christmas Breakfast Casserole

Life happens, and sometimes you just don’t have exactly what the recipe calls for, right? For the sausage in this Christmas Breakfast Casserole, feel free to swap it for cooked ham, bacon, or even a vegetarian sausage alternative. I tried a spicy Italian sausage once, and it worked… kinda! It was good, but definitely gave it a different kick. If you’re out of cheddar, a Monterey Jack or even a colby blend would be lovely. I’ve used a mix of whatever cheese I had lurking in the fridge, and it always turns out tasty. For the bread, any sturdy, day-old bread works challah, brioche, or even a crusty French loaf are all fair game. Just avoid anything too soft!

Serving Suggestions for Christmas Breakfast Casserole

Oh, the possibilities! This Christmas Breakfast Casserole is hearty enough to stand on its own, but I love to serve it with a big bowl of fresh fruit, maybe some sliced oranges and berries for a pop of color and freshness. A drizzle of maple syrup over the top is surprisingly delicious, honestly, don’t knock it till you try it! For drinks, a steaming mug of coffee or hot chocolate is a must, or maybe a festive mimosa if it’s a special occasion. This dish and a rom-com on a lazy holiday morning? Yes please! It’s the kind of meal that just begs for fuzzy socks and good company.

The Heartwarming Backstory of Christmas Breakfast Casserole

While the idea of a savory breakfast casserole isn’t tied to one specific cultural origin, this Christmas Breakfast Casserole version feels deeply rooted in the American tradition of big, comforting holiday meals. For me, it evolved from my grandma’s “everything but the kitchen sink” philosophy for holiday cooking. She’d always have a pan of something bubbly and savory baking for breakfast, using up bits and bobs from Christmas Eve dinner. It wasn’t fancy, but it was always there, a constant warmth in a bustling house. This version is my homage to her practical, loving kitchen. It’s about making a meal that feeds not just the body, but the soul, especially during a time meant for togetherness.

Frequently Asked Questions About Christmas Breakfast Casserole

→ Can I make Christmas Breakfast Casserole vegetarian?

Absolutely! Just swap the breakfast sausage for your favorite plant-based sausage or add extra veggies like mushrooms and spinach. I’ve tried it with a mix of sautéed mushrooms and it was surprisingly hearty and flavorful, honestly!

→ What kind of bread works best for this Christmas Breakfast Casserole?

Stale, sturdy bread is key! Sourdough, challah, or a good French baguette works wonderfully. I once used super soft sandwich bread and it just turned to mush, which was a bit of a kitchen disaster. Day-old is essential.

→ How do I know when my Christmas Breakfast Casserole is fully cooked?

It should be golden brown and puffed up, and a knife inserted into the center should come out clean. If it’s still jiggly, it needs more time. Don’t pull it too early, I’ve done that and had a soupy middle, oops!

→ Can I freeze this Christmas Breakfast Casserole before baking?

I haven’t personally tried freezing it unbaked, as I worry about the bread texture after thawing. I prefer to bake it first, then cool and freeze individual slices. It reheats better that way, from my experience.

→ What other cheeses can I use in this Christmas Breakfast Casserole?

Cheddar is my favorite, but Monterey Jack, Gruyere, or a blend of Italian cheeses would also be delicious. I’ve mixed in a bit of smoked gouda before, and it added a really lovely depth of flavor. Experiment a little!