Introduction
Indulge in this luxurious Creamy Spinach and Mushroom Casserole – a bubbling, golden-topped dish that combines earthy mushrooms, vibrant spinach, and a velvety cheese sauce in perfect harmony. Imagine layers of sautéed mushrooms and spinach enveloped in a rich Parmesan cream sauce, topped with buttery breadcrumbs that crisp to perfection in the oven. This elegant yet comforting casserole is ideal for holiday gatherings, potlucks, or when you need a showstopping meatless main that satisfies everyone.
Why This Casserole Will Become Your New Favorite
Restaurant-quality with home cooking simplicity
Make-ahead friendly – assemble up to 24 hours before baking
Versatile – side dish or vegetarian main course
Comfort food elegance – rich without being heavy
The magic happens when the mushrooms release their savory juices into the creamy sauce, while the spinach adds freshness and the breadcrumb topping provides the perfect textural contrast.
Ingredients for Casserole Perfection
Vegetable Base
- 1 lb cremini mushrooms (sliced)
- 10 oz fresh spinach (chopped)
- 1 medium onion (diced)
- 3 garlic cloves (minced)
Cream Sauce
- 3 tbsp butter
- 3 tbsp flour
- 2 cups whole milk
- 1 cup heavy cream
- 1 cup grated Parmesan
- ½ tsp nutmeg
- Salt & pepper to taste
Topping
- 1 cup panko breadcrumbs
- ½ cup grated Parmesan
- 2 tbsp melted butter
- 1 tsp dried thyme
Chef’s Tip: Use a mix of wild mushrooms for extra flavor depth
Step-by-Step Assembly Guide
1. Prepare the Vegetables
- Preheat oven to 375°F (190°C)
- Sauté mushrooms in batches until golden, set aside
- In same pan, wilt spinach, squeeze out excess moisture
- Sauté onion until soft, add garlic last 30 seconds
2. Make the Cream Sauce
- Melt butter in saucepan, whisk in flour to make roux
- Gradually whisk in milk and cream until smooth
- Simmer until thickened, about 5 minutes
- Remove from heat, stir in Parmesan and seasonings
3. Assemble the Casserole
- Combine vegetables in greased 9×13″ baking dish
- Pour sauce over, gently mix to distribute
- Mix topping ingredients, sprinkle evenly
4. Bake to Perfection
- Bake 25-30 minutes until bubbly and golden
- Let rest 10 minutes before serving

Professional Tips for Best Results
Don’t overcrowd mushrooms when sautéing
Warm dairy before adding to roux to prevent lumps
Freshly grate cheese for superior melting
Add fresh herbs like thyme or parsley before baking
Serving Suggestions
Elegant Presentation:
- Serve in individual ramekins
- Garnish with fresh herbs
- Accompany with lemon wedges
Perfect Pairings:
- Roasted chicken or turkey
- Crisp white wine (Chardonnay)
- Crusty artisan bread
Common Mistakes to Avoid
Skipping the spinach squeeze (makes casserole watery)
Overcooking the sauce (can become grainy)
Using pre-shredded cheese (contains anti-caking agents)
Underseasoning the sauce (needs ample salt)
Creative Variations
For Different Tastes:
- Protein boost: Add diced cooked chicken
- Vegan version: Use plant-based butter and milk
- Gluten-free: Substitute cornstarch for flour
FAQs
Q: Can I use frozen spinach?
A: Yes! Thaw and squeeze very dry (use 16 oz package).
Q: How do I store leftovers?
A: Refrigerate 3-4 days – reheat in 350°F oven.
Q: Can I freeze this casserole?
A: Yes, before baking – add topping fresh.
Q: What if I don’t have panko?
A: Regular breadcrumbs work, but won’t be as crisp.
Conclusion
This Creamy Spinach and Mushroom Casserole elevates humble ingredients into a luxurious, comforting dish that’s equally at home on holiday tables and weeknight dinner menus. With its perfect balance of textures and rich, savory flavors, it’s guaranteed to become a new family favorite.
Final Chef’s Secret: For extra decadence, add a layer of Gruyère cheese between the vegetables and sauce! The combination of earthy mushrooms, vibrant spinach, and creamy Parmesan sauce creates a vegetarian dish so satisfying, no one will miss the meat.
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Creamy Spinach and Mushroom Casserole: The Ultimate Comfort Bake
- Total Time: 40 mins
Description
Dive into this delicious Creamy Spinach and Mushroom Casserole! Rich, creamy, and packed with nutrients, it’s the perfect comfort food for any occasion.
Ingredients
2 tablespoons olive oil
1 medium onion, finely chopped
3 cloves garlic, minced
16 oz mushrooms, sliced
10 oz fresh spinach
1 cup ricotta cheese
1 cup heavy cream
1 cup grated Parmesan cheese
1/2 teaspoon nutmeg
Salt and pepper to taste
1 cup shredded mozzarella cheese
Fresh parsley, chopped (for garnish)
Instructions
Preheat the oven: Preheat your oven to 375°F (190°C).
Sauté the vegetables: In a large skillet, heat olive oil over medium heat. Add chopped onion and cook until translucent, about 5 minutes. Add minced garlic and sliced mushrooms, cooking until mushrooms are tender and browned, about 7 minutes. Add fresh spinach and cook until wilted.
Prepare the creamy mixture: In a large bowl, mix ricotta cheese, heavy cream, grated Parmesan cheese, nutmeg, salt, and pepper until well combined.
Combine and bake: Add the sautéed vegetables to the creamy mixture and stir to combine. Transfer to a baking dish and top with shredded mozzarella cheese.
Bake the casserole: Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and golden brown.
Serve: Garnish with fresh chopped parsley and serve hot.
Enjoy this rich and creamy casserole as a delightful main dish or a satisfying side!
Prep Time: 15 minutes
Cook Time: 25 minutes
Notes
This Creamy Spinach and Mushroom Casserole is a flavorful and comforting dish that will quickly become a favorite. It’s easy to make, packed with nutrients, and perfect for any meal.