Overnight Breakfast Casserole with Sausage: Easy Make-Ahead Brunch Recipe

Let me set the scene: Imagine waking up to the irresistible aroma of sizzling sausage, melted cheddar, and golden, toasty bread wafting from your kitchen. The sun’s barely peeking over the horizon, and you already know breakfast is going to be something special. That’s exactly the kind of morning this Overnight Breakfast Casserole with Sausage brings to life. The first time I pulled this bubbling beauty from the oven, I swear the smell alone could have lured the neighbors in for a taste! The top was perfectly crisp, the inside wonderfully creamy, and every bite packed with flavor.

You know those recipes that instantly become a family legend? Well, this casserole is one of them. I first stumbled onto something like it years ago at a church potluck—one of those gatherings where every dish is a secret family treasure. I was knee-high to a grasshopper, but I remember the comfort of that first cheesy, savory bite. Years passed before I tried to recreate it at home, but once I did, it was the kind of moment where you pause, take a deep breath, and just smile because you know you’re onto something truly special.

Honestly, I wish I’d discovered this overnight breakfast casserole trick years sooner. There’s nothing better than tossing everything together the night before, popping it in the fridge, and waking up to a stress-free, hot breakfast. My family can’t stop sneaking forkfuls off the edge before it even cools. And when we serve this at brunch, it’s the first dish to disappear! Whether it’s Christmas morning, a lazy Sunday, or you just want to brighten up your Pinterest breakfast board, this recipe brings pure, nostalgic comfort to your table.

I’ve tested this casserole more times than I can count (in the name of research, of course), tweaking the seasoning and cheese until it was just right. Now, it’s a staple for family gatherings, gifting, and those mornings when you want breakfast to feel like a warm hug. Trust me, you’re going to want to bookmark this one.

Why You’ll Love This Overnight Breakfast Casserole with Sausage

After years of tinkering in the kitchen—burned edges, soggy middles, and all—I can say with confidence that this Overnight Breakfast Casserole with Sausage is as close to foolproof as it gets. Here’s why it stands out from the rest:

• Quick & Easy: You assemble everything the night before in under 20 minutes. In the morning, just bake and serve. Perfect for busy families, holidays, or those mornings when coffee is all you can manage.
• Simple Ingredients: No fancy grocery trips required. Most of these are kitchen staples—think eggs, bread, cheddar, milk, and your favorite sausage.
• Perfect for Brunches and Holidays: This casserole is a lifesaver for Christmas morning, Easter brunch, or whenever you have overnight guests. It feeds a crowd and feels special without extra work.
• Crowd-Pleaser: Kids love the cheesy, comforting flavor, and adults appreciate how hearty and satisfying it is. I’ve never seen leftovers last more than a few hours.
• Unbelievably Delicious: The combo of savory sausage, sharp cheddar, and soft, custardy bread is classic comfort food. The top gets golden and a little crunchy, while the inside stays rich and creamy.

What really makes this breakfast casserole different? It’s all in the method. Letting the bread soak overnight creates a luscious, almost soufflé-like texture you can’t get from quick mixes. I like to use a mix of sharp and mild cheddar for depth, and browning the sausage until it’s just crisp adds so much flavor. You can even swap the bread for sourdough or challah for a subtle twist.

This isn’t just a good breakfast casserole—it’s the kind you’ll crave when you want something cozy, reliable, and a little bit indulgent. It’s comfort food that doesn’t make you feel weighed down, and it’s the recipe I pull out when I want smiles around the table. Whether you’re impressing guests or turning a regular Saturday into something special, this casserole has you covered.

What Ingredients You Will Need

This overnight breakfast casserole with sausage uses simple, wholesome ingredients you probably have on hand. Each one plays a part in making this casserole creamy, flavorful, and totally satisfying. Here’s the lineup:

• For the Casserole Base:
  • Bread (8 cups/400g), cubed – Day-old white sandwich bread, French bread, or sourdough. Slightly stale works best, but fresh is fine in a pinch.
  • Breakfast sausage (1 lb/450g) – Choose your favorite bulk pork sausage. I love using spicy sausage for a little kick, but mild works well for kids.
  • Cheddar cheese (2 cups/200g), shredded – Sharp cheddar gives the most flavor, but you can mix with Monterey Jack or Colby for a creamier texture.
  • Large eggs (8) – Room temperature if possible. These bind everything together and create that creamy, custardy feel.
  • Whole milk (2 cups/480ml) – For richness. You can swap in half-and-half for an even creamier result, or use 2% for a lighter casserole.
• Seasonings & Extras:
  • Dijon mustard (2 tsp/10ml) – Adds a subtle tang and depth (don’t worry, it won’t taste “mustardy”).
  • Garlic powder (1/2 tsp/2g) – Adds savory warmth without overpowering.
  • Onion powder (1/2 tsp/2g) – For a gentle, rounded flavor.
  • Salt (1/2 tsp/3g) and black pepper (1/4 tsp/1g) – Adjust to taste. If your sausage is salty, go light here.
  • Chopped fresh parsley or chives (2 tbsp/8g, optional) – For color and a fresh finish.
• For the Topping:
  • Extra shredded cheddar (1/2 cup/50g) – Sprinkled on top for a bubbly, golden crust.
  • Paprika (1/4 tsp/1g, optional) – Adds color and a hint of smokiness.

Ingredient tips: I usually grab store-brand sandwich bread, but if you have leftover artisan loaves (like sourdough), use them! For sausage, Jimmy Dean or your local butcher’s blend both work. If you need to make this gluten-free, swap in your favorite GF bread. For dairy-free, use unsweetened almond milk and a plant-based cheddar—just watch the salt levels. In summer, toss in some chopped bell peppers or spinach for extra color and nutrition.

Trust me, you don’t need anything fancy—just quality basics and a little time for all those flavors to mingle overnight.

Equipment Needed

• 9×13-inch (23×33 cm) baking dish: This is the classic size for most breakfast casseroles. If you only have a slightly smaller or larger dish, just adjust the baking time (add 5-10 minutes for a deeper casserole, shorten for a wider pan).
• Large mixing bowl: For whisking up the egg and milk mixture. I prefer glass so I can see if everything’s combined.
• Medium skillet: For browning the sausage. Nonstick or cast iron both work great—just use what you have.
• Whisk: For beating eggs. A fork will do in a pinch, but a whisk makes for fluffier custard.
• Measuring cups and spoons: Precision matters for the perfect texture.
• Aluminum foil: For covering the casserole while it rests in the fridge and for part of the baking time.
• Rubber spatula or wooden spoon: For folding together the bread, cheese, and sausage.

If you’re missing a 9×13-inch dish, two 8x8s or even a large, deep pie plate will work. I’ve used disposable foil pans for potlucks—just decrease the bake time a little. Grease your pan well (I love a quick swipe of butter). And if you’re using cast iron, let the casserole come to room temperature before baking to avoid shocking the pan. Honestly, you don’t need anything fancy—just sturdy basics you trust.

Maintenance tip: If you use ceramic or glass, avoid sudden temperature changes to prevent cracking. And if you’re on a budget, check thrift stores for extra casserole dishes. You can never have too many!

How to Make Overnight Breakfast Casserole with Sausage and Cheddar

1. Prep the bread: Cut 8 cups (about 400g) of bread into 1-inch cubes. If your bread is fresh, spread the cubes on a baking sheet and let them dry out for 30 minutes—or pop in a 300°F (150°C) oven for 10 minutes. You want the bread slightly stale so it soaks up the custard without getting mushy.
2. Brown the sausage: In a medium skillet over medium heat, cook 1 lb (450g) of sausage. Use a wooden spoon to break it into crumbles. Sauté until browned and cooked through, about 7-8 minutes. Drain any excess grease on paper towels. (Tip: If you like a little crisp, cook 1-2 minutes longer.)
3. Mix the custard: In your large mixing bowl, whisk together 8 eggs, 2 cups (480ml) whole milk, 2 tsp (10ml) Dijon mustard, 1/2 tsp (2g) garlic powder, 1/2 tsp (2g) onion powder, 1/2 tsp (3g) salt, and 1/4 tsp (1g) pepper until smooth. The mixture should be pale yellow and a little frothy on top.
4. Assemble the casserole: Grease your 9×13-inch (23×33 cm) baking dish with butter or nonstick spray. Spread half the bread cubes in an even layer. Sprinkle half the cooked sausage and half the shredded cheddar (1 cup/100g) over the bread. Layer the remaining bread, sausage, and cheese.
5. Pour the custard: Slowly pour the egg mixture evenly over the casserole, making sure all the bread is moistened. Press down gently with a spatula to help the bread soak up the custard. Sprinkle 1/2 cup (50g) extra cheddar and 1/4 tsp (1g) paprika on top.
6. Chill overnight: Cover tightly with foil and refrigerate for at least 8 hours, or up to 24 hours. (If you’re in a rush, 2 hours will do, but overnight gives the best texture.)
7. Bake: Remove the casserole from the fridge and let it sit at room temperature while you preheat your oven to 350°F (175°C). Bake, covered with foil, for 30 minutes. Remove the foil and bake another 20-25 minutes, until the top is golden and the center is set (a knife inserted in the middle should come out clean).
8. Rest and serve: Let the casserole cool for 10-15 minutes before slicing. Sprinkle with fresh parsley or chives if you like. Serve warm and watch it disappear!

Troubleshooting: If the top is browning too quickly, tent loosely with foil. If the center is still jiggly, bake in 5-minute increments until it’s set. (Don’t worry, a slightly creamy center is normal—just not runny.)

Efficiency tip: Prep all your ingredients (chop bread, shred cheese, brown sausage) before you start assembling. The overnight rest isn’t just convenient—it’s what transforms this from a regular casserole to something truly crave-worthy.

Pro Cooking Tips & Techniques

• Don’t skimp on the bread drying: If your bread is too soft, your casserole can turn soggy. Leaving it out for an hour or toasting cubes in the oven gives you that perfect, fluffy-yet-structured bite.
• Brown the sausage well: Those crispy little bits add tons of flavor. I once rushed this step and the flavor just wasn’t the same. Give the sausage a couple of extra minutes for golden edges.
• Mix up the cheeses: Using a blend (like sharp cheddar and Monterey Jack) gives you both flavor and meltiness. Pre-shredded cheese works, but grating your own melts better.
• Let it rest before baking: This step is crucial—if you bake right away, the custard won’t soak in. Overnight is best, but even a few hours makes a big difference.
• Don’t overbake: The casserole continues to cook from residual heat. Remove from the oven when the center is just set. If you wait for a super-firm center, you’ll miss out on that soft, custardy texture.
• Multitask like a pro: While the sausage browns, shred your cheese and whisk up your custard. Makes assembly a breeze!

Mistakes I’ve learned from: Once, I forgot to grease the pan and lost half the crispy top layer (not fun scraping it out!). Another time, I tried to speed things up and skipped the overnight soak—it was just okay, but not magical. Trust me, patience pays off!

Variations & Adaptations

This overnight breakfast casserole with sausage is endlessly adaptable. Here are my favorite ways to mix things up:

• Vegetarian: Swap the sausage for sautéed mushrooms, bell peppers, and spinach. You still get a hearty, flavor-packed bite.
• Gluten-Free: Use your preferred gluten-free bread (I like Canyon Bakehouse). Everything else stays exactly the same.
• Low-Carb: Ditch the bread and use roasted cauliflower florets. It’s a totally different texture—more frittata-like—but still delicious.
• Mexican-Inspired: Use pepper jack cheese, add diced green chiles, and serve with salsa and avocado.
• Holiday Twist: Add a sprinkle of dried cranberries and swap cheddar for Gruyère. Perfect for Christmas morning!
• Dairy-Free: Substitute unsweetened almond or oat milk, and use a plant-based cheese. Just taste and adjust seasonings, as some dairy-free cheeses are saltier.

Personal favorite: I once made this with leftover sourdough, apple chicken sausage, and a sprinkle of fresh sage—totally autumn in a dish! You can also try adding caramelized onions or sun-dried tomatoes for a Mediterranean flair.

Don’t be afraid to riff on this recipe. If you’ve got picky eaters or allergies, there’s always a way to make it work! Just keep the custard-to-bread ratio and let your imagination do the rest.

Serving & Storage Suggestions

This casserole is best served warm, straight from the oven. The cheese is gooey, the edges are crisp, and the aroma is basically irresistible. I like to cut generous squares and sprinkle with fresh herbs for a pop of color.

Pair it with a simple fruit salad, a pitcher of orange juice, or—if you’re feeling fancy—a sparkling brunch cocktail. It’s filling enough to stand alone, but a side of crispy hash browns or a green salad works beautifully for a bigger spread.

For storage, let leftovers cool completely. Cover tightly with foil or transfer to an airtight container and refrigerate for up to 4 days. To freeze, wrap individual pieces in plastic and then foil; freeze for up to 2 months. Reheat slices in the microwave (about 1-2 minutes per piece) or in a 350°F (175°C) oven, covered, until warmed through.

Pro tip: The flavors deepen after a day in the fridge, so don’t be shy about enjoying leftovers. If the top softens, a quick broil will bring back the crunch. Honestly, it’s just as good reheated for a quick weekday breakfast!

Nutritional Information & Benefits

Each serving (about 1/10th of the casserole) has approximately: 320 calories, 18g protein, 22g fat, 15g carbohydrates, and 1g fiber.

• Protein-rich: Thanks to sausage, eggs, and cheese, this breakfast will keep you full for hours.
• Calcium boost: Cheddar and milk pack in bone-strengthening calcium.
• Low-sugar: No added sugars, making it a smart choice for a savory breakfast.

Dietary notes: This recipe is not gluten-free as written but adapts easily. It does contain dairy and eggs, so not suitable for vegan diets. If you have a dairy allergy, swap in plant-based milk and cheese. Always check your sausage for hidden allergens.

Personally, I love starting the day with real food that tastes indulgent but gives you lasting energy. This casserole is hearty without feeling heavy—a win in my book!

Conclusion

If you’re searching for a breakfast that’s cozy, crowd-pleasing, and ridiculously easy, this Overnight Breakfast Casserole with Sausage and Cheddar is the answer. It’s the recipe I find myself making again and again—whether for lazy Saturday mornings, special occasions, or just because we all need a little more comfort food in our lives.

Don’t be afraid to make this your own. Try a different cheese, toss in your favorite veggies, or switch up the bread. The beauty of this recipe is how forgiving—and delicious—it is, no matter what.

From my family’s table to yours, I hope this casserole brings warmth, laughter, and maybe a few new traditions to your morning. If you give it a try, let me know how it turns out! Leave a comment, share your favorite variation, or tag me on social media. Here’s to breakfasts that feel like a hug in a baking dish—go ahead, make your mornings magical!

FAQs About Overnight Breakfast Casserole with Sausage

Can I assemble this casserole more than one night in advance?

It’s best to assemble the casserole no more than 24 hours ahead. Any longer and the bread can get too soggy. If you need to prep earlier, freeze the unbaked casserole instead.

What kind of bread should I use?

Any sturdy bread works! I love using day-old French or sourdough, but plain white sandwich bread is classic. Avoid super-soft breads—they soak up too much custard and go mushy.

Can I make this casserole vegetarian?

Absolutely! Just swap the sausage for sautéed mushrooms, peppers, or your favorite plant-based sausage. The flavor is still wonderful and hearty.

How do I know when the casserole is done baking?

The top will be golden and a knife inserted in the center should come out clean (a little moisture is okay, but it shouldn’t be runny). If the edges are browning too fast, cover loosely with foil.

Can I freeze leftovers?

Yes! Wrap cooled squares tightly in plastic and foil, then freeze for up to 2 months. Reheat in the microwave or oven until hot. It tastes just as comforting as the day you baked it.

Print