If you love a hearty, protein-packed breakfast that’s both delicious and easy to make, this sourdough discard breakfast casserole is about to become your new favorite morning dish. It’s the perfect way to use up extra sourdough discard while creating a flavorful, satisfying meal the whole family will love.
This casserole features a slightly tangy, soft sourdough crust topped with fluffy eggs, savory breakfast sausage (or bacon!), melted cheese, and colorful veggies. Whether you’re meal-prepping for the week or serving a crowd for brunch, this dish is a guaranteed hit!
Why You’ll Love This Recipe
-
Great use for sourdough discard – No waste, just deliciousness!
-
Super easy to make – Mix, bake, and enjoy!
-
Customizable – Use your favorite proteins, veggies, and cheeses.
-
Perfect for meal prep – Make ahead and reheat for busy mornings.
-
Crowd-pleaser – Ideal for family breakfasts or brunch gatherings.
What Does This Breakfast Casserole Taste Like?
The combination of a soft, slightly tangy sourdough crust with creamy, cheesy eggs and smoky sausage (or bacon) is pure comfort food. The edges crisp up beautifully while the center stays fluffy and rich. The cheese adds a melty, gooey texture, while the optional veggies provide a little sweetness and crunch.
Ingredients
For the Sourdough Crust:
-
1 cup (240g) sourdough discard (unfed)
-
¼ cup (60ml) milk
-
1 egg
-
½ teaspoon salt
-
½ teaspoon baking powder
-
1 tablespoon melted butter or olive oil
For the Filling:
-
6 large eggs
-
½ cup (120ml) milk
-
½ teaspoon salt
-
¼ teaspoon black pepper
-
½ teaspoon garlic powder
-
½ teaspoon onion powder
-
1 cup cooked breakfast sausage (or bacon, diced)
-
1 cup shredded cheese (cheddar, mozzarella, or a mix)
-
½ cup diced bell peppers (optional)
-
¼ cup chopped green onions (optional)
Tools You’ll Need
-
9×9-inch (or similar-sized) baking dish
-
Mixing bowls
-
Whisk
-
Spatula
-
Knife and cutting board
How to Make Sourdough Discard Breakfast Casserole
Step 1: Preheat the Oven
Set your oven to 375°F (190°C) and grease a 9×9-inch baking dish (or similar size).
Step 2: Make the Sourdough Crust
In a bowl, whisk together sourdough discard, milk, egg, salt, baking powder, and melted butter until smooth. Pour the mixture into the greased baking dish and spread evenly.
Step 3: Par-Bake the Crust
Bake the crust for 10 minutes to help it set before adding the filling. This prevents it from becoming too soggy once the eggs are added.
Step 4: Prepare the Egg Mixture
While the crust bakes, whisk together eggs, milk, salt, pepper, garlic powder, and onion powder in a separate bowl.
Step 5: Assemble the Casserole
-
Evenly sprinkle cooked sausage (or bacon), shredded cheese, and any optional veggies over the baked crust.
-
Pour the egg mixture over the top, ensuring it spreads evenly.
Step 6: Bake to Perfection
Return the casserole to the oven and bake for 25-30 minutes, or until the eggs are fully set and the top is golden brown.
Step 7: Cool and Serve
Let the casserole sit for 5 minutes before slicing. Serve warm and enjoy!
What to Serve with This Breakfast Casserole
-
Fresh fruit – Balance the savory flavors with berries, melon, or citrus.
-
Toast or biscuits – A buttery slice of toast complements the creamy eggs.
-
Hash browns or roasted potatoes – For an extra hearty meal.
-
Avocado slices or guacamole – A fresh, creamy addition.
Tips for the Best Sourdough Breakfast Casserole
-
Use a well-greased dish – This ensures easy removal and prevents sticking.
-
Let the crust set before adding eggs – It helps keep the layers distinct.
-
Prep ahead – Mix everything the night before and refrigerate. Just pop it in the oven in the morning!
-
Make it spicy – Add chopped jalapeños or a dash of hot sauce for a kick.
-
Try different cheeses – Gouda, feta, or pepper jack add fun twists.
How to Store and Reheat
Storage:
-
Keep leftovers in an airtight container in the fridge for up to 4 days.
-
Freeze individual portions for up to 2 months for easy meal prep.
Reheating:
-
Microwave: Heat slices for 30-60 seconds until warm.
-
Oven: Reheat at 350°F (175°C) for 10 minutes to keep the texture intact.
Frequently Asked Questions
Can I make this casserole the night before?
Yes! Assemble everything and store it covered in the fridge overnight. Bake in the morning, adding a few extra minutes to the bake time.
Can I make this without sourdough discard?
You can, but the sourdough adds a unique tang and depth of flavor. If omitting, replace with ½ cup all-purpose flour and ½ cup additional milk.
Can I add more veggies?
Absolutely! Mushrooms, spinach, and zucchini all work well. Just sauté them first to remove excess moisture.
Can I use turkey sausage or vegetarian options?
Yes! Turkey sausage, plant-based sausage, or extra veggies make great alternatives.
Final Thoughts
This sourdough discard breakfast casserole is the perfect balance of hearty, cheesy, and savory flavors. Whether you’re making it for a cozy weekend breakfast, a meal-prep solution, or a special brunch, it’s a guaranteed hit.
If you try this recipe, let me know how it turned out! Leave a review, share your photos on Pinterest, and tag me—I’d love to see your delicious creations!