Mushroom & Swiss Egg Bake | Breakfast Casserole
The aroma of sautéed mushrooms and melted Swiss cheese wafting from the oven is the perfect way to start a lazy Sunday morning, and that’s exactly what I experienced with this Mushroom & Swiss Egg Bake | Breakfast Casserole.
I remember making this recipe for the first time on a chilly winter morning, and the combination of earthy mushrooms, creamy cheese, and fluffy eggs was love at first bite.
It was during a particularly busy week when I realized that this Mushroom & Swiss Egg Bake | Breakfast Casserole quickly became a cherished family favorite.
Why You’ll Love This Mushroom & Swiss Egg Bake | Breakfast Casserole
- The combination of textures from the crispy edges, creamy cheese, and soft eggs is pure perfection.
- The earthy flavor of the mushrooms pairs beautifully with the nutty taste of the Swiss cheese.
- This recipe can be ready in under 45 minutes, making it perfect for busy mornings.
- The foolproof recipe ensures that you’ll get a delicious breakfast every time.
- It’s perfect for brunch gatherings or special occasions.
Ingredients You’ll Need
- 6 eggs
- 1 cup milk
- 1 cup shredded Swiss cheese
- 1/2 cup shredded cheddar cheese
- 1/2 cup cooked mushrooms
- 1/4 cup chopped onion
- 2 cloves garlic, minced
- 1 teaspoon dried thyme
- Salt and pepper, to taste
- 6 slices of bread, cubed

The star ingredients of this recipe, mushrooms and Swiss cheese, are a match made in heaven. The earthy flavor of the mushrooms complements the creamy, nutty taste of the cheese perfectly.
Expert Tips for the Best Mushroom & Swiss Egg Bake | Breakfast Casserole
- Critical technique: Sauté the mushrooms until they’re soft and fragrant to bring out their natural sweetness.
- Common mistake: Overmixing the eggs can make them tough; stop mixing once the ingredients are combined.
- Pro upgrade: Add some diced ham or bacon for added protein and flavor.
- Doneness cue: The eggs are done when they’re set and lightly golden brown on top.
- Make-ahead tip: Prepare the recipe up to a day in advance and refrigerate or freeze for later use.
Variations and Substitutions
For a gluten-free version, swap out the regular bread for gluten-free bread. You can also substitute the Swiss cheese with cheddar or feta for a different flavor profile. Add some diced jalapeños for an extra kick!

How to Store and Reheat
Store leftovers in the refrigerator for up to 3 days in an airtight container. Reheat in the microwave or oven until warmed through. You can also freeze the casserole for up to 2 months and reheat when needed.
Frequently Asked Questions
Can I make this recipe ahead of time?
Yes, you can prepare the recipe up to a day in advance and refrigerate or freeze for later use. Just reheat when you’re ready to serve.
What can I substitute for the Swiss cheese?
You can substitute the Swiss cheese with cheddar, feta, or even goat cheese for a different flavor profile.
How do I know when the eggs are done?
The eggs are done when they’re set and lightly golden brown on top.
I hope you enjoy this Mushroom & Swiss Egg Bake | Breakfast Casserole as much as my family does! Don’t hesitate to reach out if you have any questions or if you’d like any variations on the recipe.
Mushroom & Swiss Egg Bake
🧂 Ingredients
👩🍳 Instructions
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1Preheat oven to 350°F (180°C).
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2In a large skillet, sauté the mushrooms, onion, and garlic until softened.
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3In a large bowl, whisk together eggs, milk, shredded Swiss cheese, shredded cheddar cheese, thyme, salt, and pepper.
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4Add the cooked mushroom mixture to the egg mixture and stir to combine.
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5In a greased 9×13-inch baking dish, arrange half of the cubed bread in the bottom.
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6Pour half of the egg mixture over the bread, followed by half of the remaining bread, and finally the remaining egg mixture.
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7Top with the remaining bread and sprinkle with additional cheese if desired.
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8Bake for 25-30 minutes, or until the eggs are set and the bread is golden brown.

