Table of Contents

• Why You’ll Adore This Sourdough Breakfast Casserole
• Essential Ingredients for Your Breakfast Casserole
• Step-by-Step Guide to Making Sourdough Breakfast Casserole
• Pro Tips and Flavorful Variations
• Perfect Pairing: Serving Suggestions
• Storing and Reheating Your Leftovers
• More Effortless Overnight Casseroles to Explore
• Sourdough Breakfast Casserole Recipe

Why You’ll Adore This Sourdough Breakfast Casserole

• Effortless Make-Ahead Convenience: This overnight sourdough breakfast casserole is truly a game-changer for entertaining or simply enjoying a relaxed weekend. Assemble all components the evening before, pop it in the fridge, and wake up knowing breakfast is practically done. This foresight dramatically reduces morning stress, allowing you to savor extra sleep or leisurely moments before guests arrive. Just bake and serve this hearty, comforting dish.
• Irresistibly Fluffy Sourdough Base: While I love traditional hash brown casseroles, using sourdough bread in this recipe creates a uniquely satisfying texture and flavor. It’s a brilliant way to use up day-old sourdough, transforming it into soft, fluffy, flavor-soaked chunks that absorb the rich egg mixture beautifully without becoming mushy. The sourdough’s characteristic tang also adds a wonderful depth that elevates this casserole beyond the ordinary.
• Perfect for Any Gathering: Whether you’re hosting a grand holiday brunch, a casual family breakfast, or even a potluck, this casserole is designed to feed a crowd with ease. Its universal appeal makes it a guaranteed hit; I once brought it to a teachers’ appreciation lunch and received numerous emails praising its deliciousness. The combination of fluffy eggs, melted cheese, and savory sausage in every bite ensures everyone finds something to love, making it a reliable crowd-pleaser for any occasion.

Essential Ingredients for Your Breakfast Casserole

This sourdough breakfast casserole is not only a fantastic way to give new life to older sourdough bread but also an excellent recipe for utilizing a surplus of eggs. Below, you’ll find detailed notes on each key ingredient to help you perfect this dish. For the complete printable list with exact measurements and specific details, please scroll down to the comprehensive recipe card.

Step-by-Step Guide to Making Sourdough Breakfast Casserole

I genuinely love hosting, but the thought of rising at 6 AM to prepare a full breakfast for a house full of hungry guests is less than appealing. And let’s be honest, a sleep-deprived host is rarely the best company! I am many things, but an early riser is certainly not one of them, especially on a special morning!

This is precisely why I adore this sourdough breakfast bake. It streamlines your morning routine, allowing you to enjoy your holiday or weekend without the early alarm. The entire preparation process is quick and simple, done in just a few straightforward steps the night before:

• Cook the Sausage: Begin by breaking up your chosen breakfast sausage and browning it thoroughly in a hot skillet. Cook until it’s evenly browned and no pink remains. This step is crucial for flavor and texture. Once cooked, make sure to drain any excess grease to prevent the casserole from becoming oily. Set the flavorful sausage aside as you prepare the other components.
• Assemble the Casserole Layers: In a separate large bowl, whisk together the eggs, Dijon mustard, and milk until the mixture is smooth and well combined. Next, lightly grease a 13×9 inch casserole dish with non-stick spray. Spread about half of your sourdough bread cubes evenly across the bottom of the prepared dish. Sprinkle half a cup of shredded cheddar cheese over the bread, followed by all of your cooked sausage. Carefully pour the egg mixture evenly over these layers, then top with the remaining bread cubes and cheese. Gently press everything down into the egg mixture to ensure the bread fully absorbs the liquid, which is key for a tender, flavorful bake.

• Refrigerate Overnight: Once assembled, cover the casserole dish tightly with plastic wrap and place it in the refrigerator. Allowing it to chill overnight is key; it gives the bread ample time to soak up all the flavorful egg mixture, resulting in a more cohesive and tender casserole. On baking day, remember to remove the casserole from the fridge about 30 minutes to an hour before baking, allowing it to come closer to room temperature for even cooking.
• Bake to Perfection: Preheat your oven to 350ºF (175ºC). Bake the casserole for approximately 45-55 minutes, or until the top is golden brown and a knife inserted into the center comes out clean, without any wet or eggy streaks. This indicates that the eggs are fully set and cooked through. Let it rest for a few minutes before slicing and serving.

Pro Tips and Flavorful Variations

• Quickly Stale Your Bread: While day-old sourdough is ideal for soaking up the egg mixture without turning mushy, you can easily “stale” fresh bread. Simply cut it into cubes and spread it on a baking sheet. Bake in a 250ºF (120ºC) oven for 10-15 minutes, or until dried out but not toasted. Let it cool completely before using in the casserole. This ensures your bread holds its texture.
• Experiment with Proteins: The breakfast sausage is delicious, but don’t hesitate to customize! As mentioned in the Ingredients section, other ground sausages like spicy Italian or chorizo add a different flavor profile. Diced cooked ham or crispy bacon are also fantastic additions. For a meat-free alternative, try plant-based mince, or crumbled and seasoned tofu, similar to what I use in my tofu tacos, for a hearty vegetarian option.
• Boost with Veggies: Elevate the nutritional value and flavor with your favorite vegetables. Sautéed mushrooms, diced bell peppers (red, yellow, or green for color), and sweet caramelized onions are wonderful. For a touch of green, wilted spinach or kale can be folded into the egg mixture or layered into the casserole. Ensure any watery vegetables are cooked and drained before adding to prevent a soggy casserole.
• Add a Spicy Kick: If you love a bit of heat, there are many ways to spice up this casserole. Incorporate shredded Pepper Jack cheese for a subtle warmth throughout. For a more direct kick, finely diced fresh or pickled jalapeños can be added with the sausage. A pinch of red chili flakes sprinkled over the top before baking also works wonders, adding visual appeal and a gentle heat.
• Herbaceous Freshness: Fresh herbs can brighten the entire dish. A handful of chopped fresh parsley, chives, or even a sprinkle of dried Italian seasoning (oregano, basil, thyme) can be mixed into the egg mixture or sprinkled over the top before baking.
• Cheese Variety: Beyond sharp cheddar, explore other cheese combinations. A blend of cheddar and Monterey Jack offers both flavor and excellent melt. For a sophisticated touch, gruyere or fontina could also be used.

Perfect Pairing: Serving Suggestions

While this sourdough breakfast casserole is undeniably a complete meal on its own, when I’m serving a larger, hungry brunch crowd, I love to complement it with a few easy sides. Classic baked beans add a touch of sweetness and heartiness that pairs beautifully with the savory casserole. A refreshing berry fruit salad provides a light, vibrant contrast. And, of course, no festive brunch is complete without drinks: elegant raspberry mimosas for the adults and homemade Orange Julius for the kids ensure everyone has a special beverage to enjoy.

Storing and Reheating Your Leftovers

• Refrigerate: Any leftover sourdough breakfast casserole can be stored, covered tightly in an airtight container or with plastic wrap, in the refrigerator for up to 3 days. This ensures it stays fresh and delicious for easy meals throughout the week.
• Reheat: To reheat the entire casserole, cover it with foil and warm in a 350ºF (175ºC) oven until heated through, typically about 20-30 minutes, or until the center is warm. For individual servings, the microwave works perfectly; simply heat in 30-60 second intervals until warm, ensuring even heating.
• Freeze: This casserole freezes beautifully! Once cooled completely, wrap the entire casserole (or individual slices for quick meals) in a double layer of plastic wrap, then an additional layer of aluminum foil. Freeze for up to 2 months. You can reheat the casserole directly from frozen in a preheated oven (though it will take longer), or thaw it in the refrigerator overnight before reheating as usual.

More Effortless Overnight Casseroles to Explore

If you love the convenience and deliciousness of make-ahead breakfast casseroles, you’re in luck! Here are some other fantastic overnight recipes that will simplify your mornings and delight your palate:

• Croissant Baked French Toast: A decadent and flaky twist on a classic, perfect for sweet brunch lovers.
• Chocolate French Toast Bake: Indulge your sweet tooth with this rich, chocolatey morning treat.
• Ham and Potato Casserole: A hearty, savory option that’s wonderful for using up leftover ham.
• Breakfast Enchiladas: A flavorful and unique casserole inspired by Mexican cuisine.
• Blueberry Breakfast Cake: A sweet, fruit-filled cake that’s surprisingly suitable for breakfast.