Breakfast doesn’t always have to mean rushing through a bowl of cereal or grabbing something quick on the go. Sometimes, a hearty, comforting meal is exactly what you need to start the day right. That’s where the Spinach and Mushroom Breakfast Casserole shines.
This casserole is warm, savory, and satisfying — filled with earthy mushrooms, fresh spinach, protein-packed eggs, and creamy cheese. It’s the kind of recipe that works for a cozy Sunday brunch, a family breakfast, or as part of your weekly meal prep.
In this guide, we’ll explore everything you need to know about making the perfect spinach and mushroom breakfast casserole: from ingredients and substitutions to step-by-step directions, storage tips, variations, and FAQs. By the end, you’ll have a recipe that not only fits your table but also becomes part of your breakfast routine.
Why You’ll Love This Spinach and Mushroom Breakfast Casserole
- Nutritious & Wholesome – Packed with vegetables, protein, and healthy fats, it’s a balanced way to fuel your morning.
- Make-Ahead Friendly – Prepare it the night before and bake fresh in the morning. Perfect for busy weekdays.
- Customizable – Works with different cheeses, meats, or veggies depending on what you have.
- Crowd-Pleasing – Ideal for family brunches, holidays, or potlucks.
- Naturally Gluten-Free – With no bread or flour needed, this casserole fits many dietary preferences.
Ingredients You’ll Need
Here’s what makes this casserole both delicious and flexible:
- Olive Oil (1 tbsp) – For sautéing mushrooms and spinach.
- Cremini Mushrooms (16 oz, sliced) – Meaty, earthy flavor. White mushrooms also work.
- Fresh Spinach (4 cups packed) – Provides freshness, nutrients, and vibrant green color.
- Garlic (3 cloves, minced) – Adds depth and flavor.
- Green Onions (2, sliced) – Mild onion flavor that brightens the dish.
- Goat Cheese (4 oz, divided) – Creamy, tangy richness (can sub with feta, cheddar, or Gruyère).
- Eggs (12–18 large, depending on baking dish size) – The main base that holds everything together.
- Milk (½ cup) – Keeps the casserole light and fluffy. Use dairy-free alternatives if needed.
- Salt & Black Pepper – To taste.
- Fresh Chives (optional, chopped) – For garnish and a pop of color.
💡 Ingredient Note: If you prefer a milder casserole, replace goat cheese with shredded cheddar or mozzarella. For extra bold flavor, try Gruyère.
Step-by-Step Instructions
1. Prep the Baking Dish
Preheat your oven to 350°F (175°C). Grease a 9×13-inch casserole dish with nonstick spray or butter.
2. Cook the Vegetables
Heat olive oil in a large skillet over medium-high heat. Add sliced mushrooms and sauté until tender, about 4–5 minutes. Add garlic and cook for another minute until fragrant.
Stir in spinach and cook until wilted, about 2 minutes. Season lightly with salt and pepper.
3. Assemble the Casserole Base
Transfer the sautéed vegetable mixture into the prepared casserole dish. Spread evenly. Top with sliced green onions. Crumble half of the goat cheese over the top.
4. Mix the Egg Base
In a large bowl, whisk together the eggs, milk, salt, and black pepper. Pour this mixture over the vegetables.
5. Add Cheese & Bake
Sprinkle or crumble the remaining goat cheese on top. Bake uncovered for 35–45 minutes, or until the eggs are set and the edges are slightly golden.
6. Rest & Serve
Let the casserole cool for 5–10 minutes before slicing. Garnish with freshly chopped chives, if desired. Serve warm.
Serving Suggestions
This casserole is versatile and pairs well with many breakfast sides:
- Fresh fruit salad (grapes, melons, or berries).
- Crispy roasted potatoes or hash browns.
- A light side salad for brunch.
- Toast or warm crusty bread for dipping.
Variations to Try
- Cheesy Swap: Use shredded cheddar, mozzarella, feta, or Gruyère instead of goat cheese.
- Protein Boost: Add cooked bacon, sausage, or ham to the vegetable mixture.
- Veggie Mix-Up: Include bell peppers, zucchini, or caramelized onions.
- Dairy-Free Option: Use almond milk, oat milk, or coconut milk, plus dairy-free cheese.
- Spicy Kick: Add jalapeños, chili flakes, or hot sauce to the egg mixture.
Storage & Reheating
- Refrigerate: Store leftovers in an airtight container in the fridge for up to 4 days.
- Freeze: Slice into portions, wrap tightly in plastic and foil, and freeze for up to 2 months.
- Reheat: Warm in a 350°F oven for 20–25 minutes, or microwave single portions for 30–60 seconds.
👉 Tip: If reheating from frozen, thaw overnight in the fridge for best texture.
Nutrition Breakdown (Per Serving, 1 of 12)
Approximate values — may vary with substitutions.
- Calories: 165
- Protein: 12 g
- Fat: 10 g
- Carbohydrates: 4 g
- Fiber: 1 g
- Sugar: 2 g
- Sodium: 280 mg
This makes it a low-carb, high-protein breakfast option.
Frequently Asked Questions (FAQs)
1. Can I make this casserole the night before?
Yes! Assemble it, cover tightly with foil, and refrigerate overnight. Bake in the morning as directed.
2. Can I use frozen spinach?
Yes, but thaw and squeeze out excess water before using to avoid sogginess.
3. How do I know it’s fully cooked?
The eggs should be set in the center. A knife inserted should come out clean.
4. Can I double the recipe for a larger crowd?
Absolutely — use two 9×13 pans or a larger baking dish and adjust the baking time slightly.
5. How do I make it spicier?
Add diced jalapeños, crushed red pepper flakes, or even a few dashes of hot sauce.
Conclusion
The Spinach and Mushroom Breakfast Casserole is more than just a recipe — it’s a make-ahead breakfast solution that saves time while nourishing your family. With its mix of earthy mushrooms, fresh spinach, creamy cheese, and fluffy eggs, this dish is versatile, customizable, and always a crowd favorite.
Whether you’re hosting brunch, planning a holiday breakfast, or just need a quick meal-prep idea, this casserole has you covered. Try it once, and it might just become your new go-to breakfast recipe.
Recipe Card
Spinach and Mushroom Breakfast Casserole
- Prep Time: 15 mins
- Cook Time: 40 mins
- Total Time: 55 mins
- Servings: 12
- Cuisine: American
- Diet: Vegetarian, Gluten-Free
Ingredients
- 1 tbsp olive oil
- 16 oz cremini mushrooms, sliced
- 4 cups spinach leaves, packed
- 3 cloves garlic, minced
- 2 green onions, sliced
- 4 oz goat cheese, divided
- 12–18 large eggs
- ½ cup milk (or dairy-free alternative)
- Salt and black pepper, to taste
- Fresh chives, optional for garnish
Instructions
- Preheat oven to 350°F (175°C). Grease a 9×13-inch baking dish.
- In a skillet, heat olive oil. Cook mushrooms 4–5 minutes. Add garlic and spinach; cook until wilted. Season lightly.
- Spread veggies into prepared dish. Top with green onions and half the goat cheese.
- Whisk eggs, milk, salt, and pepper. Pour over vegetables.
- Crumble remaining goat cheese on top. Bake 35–45 minutes, until set.
- Let rest 5–10 minutes. Garnish with chives. Slice and serve.
