Turkey Tetrazzini with Mushrooms

The first time I made turkey tetrazzini was the day after Thanksgiving, standing in my kitchen with a container of leftover turkey that felt like both a gift and a challenge. My sister had texted asking what I was doing with it, and I decided right then to turn those pale, lonely shreds into something that would make her forget we were eating leftovers at all. An hour later, the kitchen smelled like butter, mushrooms, and cream, and I knew I'd stumbled onto something worth repeating.

I made this for a dinner party once when I was feeling ambitious but not confident, and it was exactly what I needed—something I could mostly prepare ahead and just slide into the oven when friends arrived. While they were opening wine and settling into the living room, I was popping the casserole in to bake, and by the time I called everyone to the table, the golden top was bubbling at the edges just right. That dish disappeared so quickly that I barely had time to feel proud of myself.

Ingredients

• Spaghetti or linguine (340 g / 12 oz): The pasta is your canvas here, and cooking it just to al dente means it won't turn to mush when baked.
• Unsalted butter (4 tbsp): This is where the sauce gets its soul—use real butter, not margarine.
• Yellow onion and garlic (1 medium onion, 3 cloves): These are your flavor foundation, softening into the butter until they're sweet and mellow.
• Cremini or white mushrooms (250 g / 9 oz): Sliced mushrooms release their moisture as they cook, which builds the sauce's depth; don't rush this step.
• All-purpose flour (4 tbsp): This creates the roux that thickens your sauce from thin to silky.
• Whole milk, chicken broth, and heavy cream (720 ml milk, 120 ml broth, 120 ml cream): The ratio here is crucial—the milk is the bulk, the broth adds chicken-y depth, and the cream makes it luxurious.
• Kosher salt, black pepper, and ground nutmeg: Nutmeg is the secret whisper that makes people ask what's in it.
• Cooked turkey (400 g / 3 cups): Use leftover roasted turkey cut into bite-sized pieces, or shred it if you prefer.
• Frozen peas (180 g / 1 cup): Thaw them first so they stay tender and don't add icy pockets to your bake.
• Parmesan and mozzarella cheese (70 g Parmesan, 120 g mozzarella): The Parmesan brings salt and sharp flavor, while mozzarella melts into creamy pools.
• Fresh parsley (2 tbsp): This bright green note keeps the whole dish from feeling too heavy.
• Panko breadcrumbs, melted butter, and Parmesan for topping (60 g panko, 2 tbsp butter, 2 tbsp Parmesan): This crust toasts to golden and gives you that textural contrast.

Instructions

Get your oven ready and prep your pan:

Preheat your oven to 190°C (375°F) and lightly grease a 23x33 cm (9x13-inch) baking dish with butter or oil. This prevents the edges from sticking and gives you clean portions when you serve.

Cook the pasta until just al dente:

In a large pot of salted boiling water, cook your spaghetti or linguine until it still has a slight resistance when you bite it. Drain it well and set it aside—don't rinse it, because that starch will help the sauce cling to each strand.

Build your flavor base with butter and vegetables:

Melt butter in a large skillet over medium heat and add your finely chopped onion. Let it soften for about 3 minutes until it turns translucent, then add the minced garlic and let that bloom for about 30 seconds. Add your sliced mushrooms and cook, stirring often, for 6 to 8 minutes until they turn golden and any liquid they release has evaporated—this deepens their flavor.

Create the roux that will thicken your sauce:

Sprinkle the flour over your vegetables and stir constantly for 1 to 2 minutes. You're looking for a smooth, paste-like mixture that coats the bottom of the pan; this is your roux, and it's the bridge between watery and silky.

Slowly add your liquids and whisk until smooth:

Pour in the milk, broth, and cream gradually while whisking continuously, working out any lumps as you go. This patience pays off because lumpy sauce is nobody's friend. Bring the mixture to a gentle simmer and keep stirring for about 5 minutes until it thickens enough to coat the back of a spoon.

Season and fold in your filling ingredients:

Remove the pan from heat and season with salt, pepper, and a pinch of nutmeg. Stir in your cooked turkey, thawed peas, Parmesan, mozzarella, and fresh parsley until everything is evenly distributed. Fold in your cooked pasta last, using a large spoon to gently combine everything without breaking the noodles.

Transfer to your baking dish:

Pour the entire mixture into your prepared baking dish and smooth the top with the back of a spoon.

Make and scatter your breadcrumb topping:

In a small bowl, stir together your panko breadcrumbs, melted butter, and grated Parmesan until the crumbs are evenly moistened and clumpy. Sprinkle this mixture over the top of your casserole in an even layer, leaving some gaps so the cream bubbles up around the edges.

Bake until golden and bubbling:

Bake uncovered for 25 to 30 minutes until the top is golden brown and the filling is bubbling up around the edges. You'll know it's done when the whole thing looks warm and inviting and smells impossible to resist.

Rest before serving:

Let the casserole sit for 10 minutes after pulling it from the oven. This allows the filling to set slightly so you can cut clean portions, and it gives the flavors a moment to settle.

Save

There was an evening when I made this for my neighbor who had just come home from the hospital, and watching her face when she took that first forkful—the way her eyes closed for a second like she was collecting herself—made me understand that food sometimes heals in ways that have nothing to do with nutrition. She told me later she'd had thirds, which felt like the best compliment I could get.

Why This Dish Matters

Turkey tetrazzini exists in that perfect space between comfort and elegance, which is why it's shown up on dinner tables for generations. It's the kind of dish that works equally well for a Tuesday night when you need something warm, or for a Saturday dinner when you want to feed people something that feels special. The beauty of it is that it hides the fact that you might be working with leftovers, turning them into something that tastes intentional and made-with-love.

Building Layers of Flavor

This recipe works because it builds flavor in layers rather than dumping everything together and hoping for the best. The butter releases the sweetness in the onions, the onions and garlic create a savory base, the mushrooms add umami depth, and the cheese at the end brings richness and salt. Each step matters, and you can taste it when you've done it right—the sauce doesn't taste like cream pretending to have flavor, it tastes like you actually made something.

Making It Your Own

The recipe I've given you is reliable and will work every time, but once you've made it once, you'll start seeing variations. Some people add a splash of dry sherry or white wine to the sauce for brightness, or stir in a handful of fresh spinach for color and nutrition. Others use rotisserie chicken instead of turkey, or swap the peas for broccoli florets, or even add crispy bacon crumbled over the top.

• If you want a crispier topping, broil the casserole for 2 to 3 minutes right at the end, watching carefully so the crumbs don't burn.
• Make this a day ahead and bake it the next day—the flavors actually meld together beautifully overnight, and it's one less thing to do when people are coming over.
• Double the recipe and freeze one casserole unbaked so you have a homemade frozen dinner that feels like a gift to your future self.

Save

Every time I make this, I'm reminded that the best recipes are the ones that taste like someone cared enough to pay attention. That's what this dish does—it rewards you for slowing down just a little.

Common Recipe Questions

→ What type of pasta works best for this dish?

Spaghetti or linguine are ideal as they hold the creamy sauce well and create a balanced texture with the other ingredients.

→ Can I substitute the turkey with another protein?

Yes, rotisserie chicken can be used as a flavorful alternative that complements the creamy sauce and vegetables.

→ How do I achieve a crispy topping on the bake?

Mix panko breadcrumbs with melted butter and grated Parmesan, then sprinkle evenly before baking. For extra crispiness, broil for 2-3 minutes at the end.

→ Is it possible to make a gluten-free version?

Absolutely, by using gluten-free pasta and substituting all-purpose flour with a gluten-free alternative, you can enjoy a similar creamy texture.

→ What flavor enhancements complement the sauce?

A splash of dry sherry or white wine added during sauce preparation adds depth and brightens the flavor profile.