This Mushroom Spaghetti is made with browned cremini mushrooms tossed with spaghetti in a classic bechamel sauce, finished with a good amount of parmesan. Bechamel gives this a thicker, more velvety coating than a cream-based sauce, closer to what you’d find under a baked pasta dish.

I make this when I want something that feels a little more restaurant-style without much extra effort, since bechamel comes together in about 10 minutes on the stove. It’s also a good way to use up mushrooms before they go soft in the fridge. I like serving this next to Broccoli Bacon Alfredo Pasta or Homemade Hamburger Macaroni and Cheese for a bigger pasta night spread.

If you like creamy, comforting pasta dinners like this one, these are worth trying too:

Mushroom Spaghetti Pasta with Bechamel Sauce

Ingredients You’ll Need

Cremini mushrooms have more flavor than white button mushrooms, though either works here. Whisking the milk into the roux gradually is what keeps a bechamel smooth instead of lumpy.

Ingredients

12 oz spaghetti
2 tbsp olive oil
1 lb cremini mushrooms, sliced
1 small onion, diced
2 cloves garlic, minced
3 tbsp butter
3 tbsp all-purpose flour
2 cups milk
1/2 cup grated parmesan cheese, plus extra for serving
1/4 tsp ground nutmeg
Salt and pepper, to taste
Chopped fresh parsley, for serving

Directions

Bring a large pot of salted water to a boil and cook the spaghetti according to the package instructions until al dente.
Drain and set aside.
While the pasta cooks, prepare the mushrooms and sauce.
Heat the olive oil in a large skillet over medium-high heat.
Add the mushrooms and cook for 8 to 10 minutes, stirring occasionally, until browned and any released liquid has evaporated.
Don’t rush this step – browned mushrooms have a much deeper flavor than ones that just went soft and pale.
Add the onion to the skillet and cook for 4 to 5 minutes, until softened.
Stir in the garlic and cook for 30 seconds, just until fragrant.
Transfer the mushroom mixture to a bowl and set aside.
In the same skillet, melt the butter over medium heat.
Whisk in the flour and cook for about a minute, stirring constantly, to cook off the raw flour taste.
Slowly whisk in the milk, a little at a time, continuing to whisk until the sauce thickens, about 4 to 5 minutes.
Stir in the parmesan cheese and nutmeg, whisking until the cheese melts into the sauce.
Season with salt and pepper.
This one takes a bit of attention while whisking, just so you know, since a bechamel can go lumpy fast if you stop stirring.
Return the mushroom mixture to the skillet along with the drained spaghetti.
Toss everything together until the pasta is evenly coated in the sauce.
Serve immediately, topped with extra parmesan and fresh parsley, and enjoy!

Important Recipe Notes

Brown the mushrooms properly. This is the step that builds the most flavor in the whole dish. Give them the full 8 to 10 minutes to develop good color before moving on.
Whisk constantly while making the bechamel. Stopping to do something else, even for a minute, is how you end up with lumps. Have everything else ready before you start this step.
Add the milk gradually, not all at once. Pouring it in slowly while whisking is what keeps the sauce smooth instead of separating.
This sauce thickens as it cools, so if you’re not serving right away, thin it with a splash of milk when reheating.
Store leftovers in an airtight container in the fridge for up to 3 days. Reheat gently on the stove with a splash of milk to loosen the sauce back up.
This doesn’t freeze particularly well, since bechamel-based sauces tend to separate after thawing. It’s best enjoyed fresh or within a few days.

How to Serve, Store & Customize This Recipe

Serving: Serve immediately while hot, topped with extra parmesan and a sprinkle of fresh parsley. This works well as a main on its own or alongside a simple green salad.

Storing: Keep leftovers in an airtight container in the fridge for up to 3 days. Reheat gently on the stove over low heat, adding a splash of milk to bring the sauce back together.

Customizing: Add cooked chicken or Italian sausage for extra protein, or stir in a handful of baby spinach at the end for more greens. A pinch of smoked paprika in the mushrooms adds a subtle smoky note.