This Mushroom Lasagna Bake is rich, creamy, and deeply savory, without a hint of meat. It’s the kind of vegetarian comfort food that makes even the most devoted carnivores ask for seconds.

A mix of sautéed cremini and shiitake mushrooms, garlic, and fresh thyme gets layered with silky béchamel, lasagna noodles, and three cheeses. Everything bakes until bubbly and golden, and the hardest part is waiting for it to rest before you slice into it.

What Makes This Mushroom Lasagna So Good

I’ll be honest: this is not a 30-minute weeknight dinner. But most of the time is hands-off while the oven works, and the payoff is a lasagna that holds together in neat, creamy slices with those irresistible crispy edges at the top.

A blend of cremini and shiitake mushrooms gives the filling real depth: earthy, a little chewy, and nothing like the watery disappointment some vegetable lasagnas turn into. Browning them well in butter and deglazing with a splash of white wine pulls out every bit of savory flavor.

The béchamel stays luscious after baking because I keep the ratio of milk to roux on the thicker side and season it simply with nutmeg and Parmigiano-Reggiano. No broken sauce, no pool of liquid sitting in the bottom of the pan.

Ingredients

1 lb (450g) cremini mushrooms, sliced: creminis give a meaty base without any grit
8 oz (225g) shiitake mushrooms, stems removed, caps sliced: adds depth and a little chew
1 large yellow onion, finely diced: melts into the mushroom filling
4 cloves garlic, minced: use fresh for the best flavor
3 tbsp unsalted butter, divided: for sautéing and for the béchamel
1/4 cup dry white wine, optional: lifts all the savory notes; skip or use broth
2 tsp fresh thyme leaves: dried thyme works but use only 1 tsp
4 tbsp all-purpose flour: thickens the béchamel
4 cups whole milk, warmed: cold milk added all at once can make the sauce grainy
1/8 tsp ground nutmeg: a tiny amount wakes up the dairy
12 dried lasagna noodles: regular noodles, boiled; you can use no-boil if you adjust the liquid
1 1/2 cups whole milk ricotta: full-fat ricotta gives the best creamy texture
1 large egg: binds the ricotta mixture
2 cups shredded low-moisture mozzarella: melts into stretchy, golden pockets
1 cup finely grated Parmigiano-Reggiano: divided between filling and topping
Salt and freshly ground black pepper: season at every layer

Variations / Substitutions

Protein: if you want meat, brown 1/2 lb crumbled Italian sausage with the mushrooms
Herbs: swap fresh thyme for 1 tsp fresh chopped rosemary or sage
Spinach: stir 2 cups packed baby spinach into the hot mushrooms until wilted, then carry on
Cheese: part-skim mozzarella works fine; the top just won’t brown quite as deeply
Dairy-free: use plant-based butter, unsweetened oat milk for the béchamel, and your favorite melting vegan cheese

If a quicker pasta is what you need tonight, a Mushroom and Spinach Stovetop Lasagna comes together in half the time with no oven needed.

How to Make Creamy Mushroom Lasagna Bake

Step 1: Brown the Mushrooms

Get a large skillet hot over medium-high heat. Melt 2 tbsp of the butter, then add the sliced cremini and shiitake mushrooms in a single layer. Let them sit undisturbed for about 4 minutes, until the undersides develop a deep brown color. Stir and cook another 4 to 5 minutes, until all the liquid they release has cooked off and the mushrooms look glossy and golden.

Don’t rush this part. The mushrooms will steam if the pan is too crowded or you stir them too early. Work in two batches if your skillet isn’t wide enough to hold them in a single layer.

When the mushrooms are well browned, push them to one side of the pan. Add the diced onion to the cleared spot and cook for 3 minutes, until it softens and turns translucent. Stir in the minced garlic and thyme, and cook 1 minute more. Pour in the white wine, if using, scrape up any browned bits stuck to the bottom, and let it bubble away almost completely. Season with 1/2 tsp salt and a few grinds of black pepper. Remove the skillet from the heat.

Step 2: Build the Béchamel

In a medium saucepan, melt the remaining 1 tbsp of butter over medium heat. Whisk in the 4 tbsp flour and cook, whisking constantly, for 1 minute. The mixture will foam and smell lightly nutty. Start pouring in the warmed milk in a slow, steady stream while you whisk. Once all the milk is in, keep whisking until the sauce comes to a gentle bubble and thickens enough to coat the back of a spoon. This takes about 4 to 5 minutes.

Take the pan off the heat. Stir in the nutmeg, 1/2 cup of the grated Parmigiano, and a generous pinch of salt. Taste it; the béchamel should be well seasoned because this is what carries flavor through the whole lasagna. Pour about 1/2 cup of the béchamel into a small bowl and save it for the top layer, then set the rest aside.

Warm milk is the key here. Cold milk dumped into a hot roux can seize up and make a lumpy sauce. You can heat it in a glass measuring cup in the microwave for 2 minutes while the mushrooms cook.

Step 3: Mix the Ricotta Filling

In a medium bowl, combine the ricotta, egg, the remaining 1/2 cup of Parmigiano, 1/2 tsp salt, and a few cracks of black pepper. Stir everythign together until smooth. Fold in about a third of the sautéed mushroom mixture. This makes the ricotta layer far more interesting than it would be on its own.

The egg firms the ricotta up during baking so the slices hold their shape. If you skip it, the filling will be looser and more likely to spill out when you cut.

You can do this step and the mushrooms up to a day ahead and refrigerate both. Bring them to room temperature before you assemble the lasagna.

Step 4: Layer the Lasagna

Cook the lasagna noodles in a large pot of salted boiling water for 2 minutes less than the package directs. They’ll finish cooking in the oven. Drain and rinse them under cold water to stop the cooking and make them easier to handle.

Spoon a thin layer of béchamel across the bottom of a 9×13 inch baking dish. Lay down 4 noodles, overlapping them slightly if needed. Spread half the ricotta mixture over the noodles, then scatter half the remaining mushroom mixture on top. Sprinkle with 1/3 of the shredded mozzarella. Spoon about a third of the béchamel over that. Repeat the layers: 4 noodles, remaining ricotta, remaining mushrooms, another 1/3 of the mozzarella, and another third of the béchamel. Top with the last 4 noodles, the reserved 1/2 cup béchamel, and the final mozzarella.

The last layer of béchamel spread all the way to the edges stops the top noodles from curling and drying out during the bake.

Step 5: Bake It Covered, Then Uncovered

Preheat the oven to 375°F (190°C) if you haven’t already. Cover the dish tightly with aluminum foil, tenting it slightly so the foil doesn’t stick to the cheese. Bake for 35 minutes. The noodles will soak up the sauce and the ricotta will set.

Remove the foil and bake uncovered for another 15 to 20 minutes. You’re looking for a golden, bubbling top with dark spots here and there. If you want an extra browned surface, switch the broiler on for the last 2 minutes, but stand right there; it goes fast.

Pull the dish from the oven. This next part matters: let it rest on the counter for at least 15 minutes. Cutting straight away sends hot filling spilling onto the plate, and the slices won’t stay stacked.

Step 6: Slice and Serve

Run a sharp knife through the lasagna into 8 portions and use a flat spatula to lift each piece out. The first slice will be the messiest, and that’s normal. After that, they come out in clean, creamy layers with the mozzarella pulling in long strands.

Finish each plate with a few cracks of black pepper and a little extra Parmigiano if you like. Serve it right away while the center is still warm and the top edges keep their crunch.

Tips for the Best Mushroom Lasagna

Use two kinds of mushrooms if you can. Creminis on their own are fine, but the shiitakes add a texture that stops the filling from feeling one-note.
Sauté the mushrooms in a pan that gives them room. Overcrowding traps steam, and then they never brown. A 12-inch skillet is the minimum.
If you use no-boil noodles, stir 1/2 cup water into the béchamel before layering, and make sure the bottom of the dish is well coated. Those noodles need extra moisture to soften properly.
Let the baked lasagna rest. Even 10 minutes makes a real difference in how cleanly it cuts.

Keeping Mushroom Lasagna Fresh

Refrigerate: cool the lasagna completely, then cover the dish or transfer slices to an airtight container. It keeps for up to 4 days.
Reheating: warm individual portions in the microwave for 2 to 3 minutes, or cover the whole dish with foil and reheat in a 350°F (175°C) oven for 20 minutes.
Freeze: you can freeze the fully baked and cooled lasagna. Wrap it tightly and freeze for up to 2 months. Thaw overnight in the fridge before reheating.

What to Serve with Mushroom Lasagna Bake

A simple arugula salad with lemon and olive oil cuts through the richness of the béchamel and cheese, and you can toss it together in the 15 minutes the lasagna rests. Garlic bread is the obvious companion if you want something to catch every last smear of sauce. For a lighter side, roasted asparagus or broccolini with a squeeze of lemon keeps the meal from feeling too heavy.

Frequently Asked Questions

Can I assemble the lasagna a day ahead?

Yes. Build the whole dish up to the final mozzarella layer, cover, and refrigerate it overnight. Add 10 minutes to the covered baking time since you’ll start from cold.

Can I freeze unbaked lasagna?

You can, but I get better results freezing it already baked. The texture of the ricotta and béchamel stays smoother that way. Assemble, bake, cool completely, then wrap and freeze. Thaw in the fridge and reheat covered in a warm oven.

What if I only have all-purpose flour for the béchamel?

That’s exactly what this recipe uses. All-purpose flour makes a perfectly smooth sauce here. Avoid whole wheat or bread flour; their higher protein can make the béchamel feel a little gummy.

Can I use part-skim ricotta?

Yes. The lasagna will still be creamy, just a touch less rich. I wouldn’t use fat-free ricotta, though. It can turn watery and grainy in the oven.