Creamy Spinach and Mushroom Lasagna | Easy Vegetarian Comfort Food

Looking for a hearty, meatless meal that feels like a warm hug? Creamy spinach and mushroom lasagna is the ultimate easy vegetarian comfort food. With layers of tender noodles, sautéed mushrooms, creamy ricotta, and velvety béchamel, it’s rich, cheesy, and totally satisfying — without any meat. Whether you’re a vegetarian or just craving something cozy and delicious, this lasagna delivers big flavor with simple ingredients. It’s perfect for weeknight dinners, meal prep, or feeding a hungry crowd. In this guide, you’ll get step-by-step tips, tasty variations, and answers to common questions about making the best white vegetarian lasagna ever.

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Ingredients for Creamy Spinach and Mushroom Lasagna

This easy vegetarian comfort food comes together with a handful of pantry staples and fresh ingredients. Here’s everything you’ll need to make a creamy spinach and mushroom lasagna that’s rich, flavorful, and totally satisfying.

Fresh and Pantry Staples You’ll Need

🧅 Vegetables

• 16 oz frozen spinach, thawed and squeezed dry
  Packed with nutrients and perfect for layering.
• 8 oz white mushrooms, finely chopped
  Adds a meaty texture and savory depth.
• ½ cup white onion, finely diced
  Brings a sweet, aromatic base to the filling.
• 6 garlic cloves, minced
  Because every good lasagna needs garlic — lots of it.

🧀 Cheeses

• 30 oz whole milk ricotta
  Creamy, smooth, and ideal for that melt-in-your-mouth filling.
• ½ cup Parmigiano Reggiano, freshly grated
  For a nutty, salty kick — grate it fresh for the best flavor.
• 8 oz low-moisture mozzarella, shredded and divided
  Melts beautifully and gives that irresistible cheesy pull.

🥛 White Sauce (Béchamel) Ingredients

• 5 tbsp unsalted butter
• 5 tbsp all-purpose flour
• 5 cups whole milk, room temperature
• ½ tsp ground nutmeg
  Adds warmth and depth to the sauce.
• ½ tsp black pepper
• 1 tsp kosher salt, or to taste
• ½ cup grated Parmesan, stirred in at the end

Need help making a smooth, lump-free béchamel? Follow this step-by-step guide on how to make béchamel sauce — it’s beginner-friendly and foolproof.

🍳 Other Must-Haves

• 2 large eggs
  Helps bind the ricotta filling together.
• ¼ cup fresh parsley, chopped
  Adds freshness and color.
• 1 lb lasagna noodles
  Cooked al dente for perfect layering. No-boil noodles can work too, with adjustments.
• Olive oil (optional)
  To drizzle on noodles after cooking so they don’t stick.

How to Make Creamy Spinach and Mushroom Lasagna Step by Step

Making lasagna from scratch might sound intimidating, but this version is surprisingly doable — even on a busy weeknight. The trick? Prep your layers in advance and follow these easy, bite-sized steps. Let’s build this creamy vegetarian comfort food masterpiece from the bottom up.

Prep Your Ingredients First

1. Thaw and Drain the Spinach

Let’s start with the greens. If you’re using frozen spinach, let it thaw completely. Then, squeeze out as much water as you can using a clean dish towel, cheesecloth, or a steamer basket trick. Dry spinach = no soggy layers.

2. Cook the Lasagna Noodles

Boil 1 lb of lasagna noodles until just al dente — about 2 minutes less than the package says. Drain and rinse with cold water. Lay the noodles flat on parchment paper and drizzle lightly with olive oil so they don’t stick together.

Make the Savory Mushroom and Spinach Filling

3. Sauté Onions, Garlic, and Mushrooms

In a large skillet, melt 4 tbsp of butter over medium-high heat. Add diced white onion, salt, and pepper, then cook for 2–3 minutes. Stir in minced garlic, then toss in your chopped mushrooms and Italian seasoning. Sauté everything until mushrooms are browned and most of their moisture has evaporated — about 7–10 minutes.

4. Add the Spinach

Turn off the heat. Stir in the drained spinach until evenly combined. Season again to taste.

Create the Creamy Ricotta Mixture

5. Mix the Cheesy Goodness

In a large bowl, combine:

• 30 oz ricotta
• 2 eggs
• ½ cup grated Parmesan
• ¼ cup chopped parsley
• Half of your shredded mozzarella

Once the mushroom-spinach mixture has cooled slightly, fold it into the ricotta blend.

Whip Up the Creamy White Béchamel Sauce

6. Make a Simple Roux

In a heavy saucepan, melt 5 tbsp butter over medium heat. Whisk in 5 tbsp flour until it forms a smooth paste — that’s your roux. Let it cook for about a minute to remove any raw flour taste.

7. Add the Milk Slowly

Gradually pour in 5 cups of room-temp whole milk, whisking constantly. Go slow — this keeps it smooth. Let the sauce thicken as it heats (about 5–7 minutes).

8. Finish the Sauce

Once thickened, stir in ½ tsp nutmeg, salt, pepper, and ½ cup grated Parmesan. You want it just thick enough to coat the back of a spoon — silky, not gluey.

Assemble the Lasagna Layers

9. Layer Like a Pro

Preheat your oven to 375°F (190°C). Spread a thin layer of white sauce on the bottom of a 9×13 baking dish.

Then repeat the following:

• A layer of noodles
• A generous scoop of the ricotta-spinach-mushroom mixture
• A drizzle of béchamel
• A sprinkle of mozzarella

Repeat until all ingredients are used. Finish with a final noodle layer, the rest of the white sauce, and top with remaining mozzarella.

Bake to Golden, Cheesy Perfection

10. Cover and Bake

Lightly grease a piece of foil and cover the lasagna (greased side down). Bake for 30 minutes, then remove foil and bake for another 10–15 minutes, until the top is bubbling and lightly browned.

Optional: Broil for 1–2 minutes for a golden cheese crust — but keep a close eye!

Let It Rest Before Serving

11. Cool for Clean Slices

Remove from the oven and let it rest for 15 minutes before slicing. This helps everything set and keeps your layers beautifully intact.

Tools You’ll Need for Creamy Spinach and Mushroom Lasagna

You don’t need fancy gadgets to make this easy vegetarian comfort food. Just a few basic kitchen tools can help you prep, layer, and bake like a pro. Here’s what you’ll want to have on hand before you dive in.

Must-Have Tools for Lasagna Success

🥘 Large Non-Stick Skillet or Sauté Pan

Perfect for cooking down your onions, garlic, mushrooms, and spinach. A wide pan gives the mushrooms space to brown without steaming.

🧀 Mixing Bowls

You’ll need at least two — one for the ricotta mixture and one for combining the spinach and mushroom filling.

🥄 Whisk

Essential for making a smooth, lump-free béchamel sauce. A balloon whisk works best for incorporating flour and milk evenly.

🫕 Medium to Large Saucepan

Use this for cooking the roux and whisking in the milk to make your creamy white sauce.

🍝 Large Pot for Boiling Pasta

A stockpot will help cook lasagna noodles evenly. Don’t forget a drizzle of olive oil after draining to keep them from sticking.

🍽 9×13-inch Baking Dish

This is your lasagna’s final destination. Choose an oven-safe dish that’s deep enough for multiple layers of cheesy, creamy deliciousness.

Want a recommendation? This classic 9×13 baking pan is versatile and ideal for both baking and serving.

🔪 Chef’s Knife & Cutting Board

For finely chopping mushrooms, onions, and fresh herbs like parsley or basil.

🧻 Parchment Paper or Kitchen Towels

Helpful for laying out cooked noodles so they don’t stick together while you assemble the layers.

🧤 Foil & Nonstick Spray

Use foil to cover the lasagna during baking — just spray the inside so the cheese doesn’t stick to it.

Frequently Asked Questions About Creamy Spinach and Mushroom Lasagna

Wondering if you can freeze it, tweak it, or make it ahead? You’re not alone. These FAQs cover the most common questions people ask before diving into a creamy spinach and mushroom lasagna recipe — so you can cook with confidence.

Can I make creamy spinach and mushroom lasagna ahead of time?

Yes, absolutely! This dish is perfect for prepping in advance. You can fully assemble the lasagna, cover it tightly with foil, and refrigerate it for up to 24 hours before baking. Just add an extra 10–15 minutes of baking time if you’re pulling it straight from the fridge.

Can I freeze this lasagna?

You bet! After baking and cooling, slice it into individual portions and wrap them tightly in plastic wrap or foil. Store in an airtight container in the freezer for up to 3 months. To reheat, thaw overnight in the fridge and warm in the oven at 350°F until heated through.

How do I reheat leftovers without drying it out?

The secret? Cover it! Reheat individual portions in the microwave with a damp paper towel on top, or warm the whole tray in the oven, covered with foil, at 350°F for about 20–25 minutes. Add a splash of milk if it looks a little dry.