Recipe for Chicken Tetrazzini Bake: Cheesy Pasta Casserole with Mushrooms

This chicken tetrazzini bake transforms simple ingredients into a creamy, comforting casserole that’s perfect for family dinners.

I developed this version after testing multiple recipes, focusing on the ideal balance of tender pasta, shredded chicken, and earthy mushrooms in a rich cheese sauce.

The dish bakes until golden and bubbly, with a crisp topping that contrasts beautifully with the velvety interior.

It’s a one-dish meal that’s easy to assemble and even easier to love. Here’s how to make it.

Ingredients for Recipe for Chicken Tetrazzini Bake

Pantry staples and a few fresh picks create this cozy, cheesy casserole everyone will devour.

The pasta is key here—De Cecco or Barilla fettuccine hold up best to baking without turning mushy. For the chicken, Costco rotisserie is a great shortcut (pull the meat, discard the skin). Mushrooms should be fresh and firm; creminis add more flavor than whites. The Parmesan? Grab a wedge from Whole Foods and grate it yourself—pre-shredded just doesn’t melt the same.

No sherry? Extra chicken broth plus a splash of lemon juice works. Swap cremini for baby bella or white mushrooms if needed. The cheddar can be Monterey Jack for milder flavor. Out of panko? Crushed Ritz crackers or regular breadcrumbs in a pinch. Full-fat milk is ideal, but 2% in a 1:1 swap still yields good results (just slightly less rich).

Assemble up to 24 hours ahead and refrigerate—just add 10-15 extra minutes to baking time. Leftovers keep 4-5 days in the fridge or freeze for 3 months (thaw before reheating). The breadcrumb topping stays crisp if you broil the last 2 minutes.

Step-by-Step Instructions for Chicken Tetrazzini Bake

Here’s how to layer flavors and textures for a casserole that’s creamy, crispy, and irresistibly comforting.

Step 1: Cook the Chicken and Pasta

Preheat your oven to 375°F. While it heats, season the 1.5 lb boneless, skinless chicken breasts with 1 tsp salt and 0.5 tsp black pepper. Poach them in simmering chicken broth for 12-15 minutes until internal temperature reaches 165°F.

Remove the chicken and shred it using two forks. In the same pot, cook the 12 oz fettuccine pasta in the flavored broth for 8-10 minutes until al dente. Drain, reserving 1 cup of the broth for the sauce.

Step 2: Sauté Mushrooms and Prepare the Roux

In a large skillet, melt ¼ cup of the unsalted butter over medium heat. Add the 8 oz cremini mushrooms and cook for 5-6 minutes until golden brown and tender. Stir in the 3 cloves minced garlic and cook for 30 seconds until fragrant.

Push the mushrooms to one side and add the remaining ¼ cup unsalted butter. Once melted, whisk in the 0.33 cup all-purpose flour to form a roux. Cook for 1-2 minutes until light golden and bubbly.

Step 3: Build the Creamy Sauce

Gradually whisk in the 2 cups whole milk and reserved 1 cup chicken broth, ensuring no lumps form. Stir in the 0.25 cup dry sherry or white wine and 1 tbsp Dijon mustard. Simmer for 3-4 minutes until the sauce thickens enough to coat the back of a spoon.

Reduce heat to low and stir in ½ cup of the shredded sharp cheddar cheese and all of the 1 cup shredded Parmesan cheese until melted and smooth. Taste and adjust seasoning if needed.

Step 4: Assemble and Bake the Casserole

In a large bowl, combine the cooked fettuccine, shredded chicken, mushroom mixture, and creamy sauce. Mix until everything is evenly coated. Transfer to a greased 9×13-inch baking dish.

In a small bowl, mix the remaining ½ cup shredded sharp cheddar cheese with the 0.5 cup panko breadcrumbs. Sprinkle this mixture evenly over the casserole.

Step 5: Bake to Perfection and Serve

Bake uncovered for 20-25 minutes until the top is golden brown and the edges are bubbling. If the topping browns too quickly, tent with foil.

Let the casserole rest for 5 minutes before serving. Garnish with 0.25 cup fresh parsley for a pop of color. The sauce should be creamy, the topping crisp, and every bite packed with rich, cheesy flavor.

Essential Equipment for This Dish

Baking Dish Essentials

For this casserole, a 9×13-inch baking dish is ideal—I use my Le Creuset stoneware for even heat distribution. Glass dishes work too, but avoid thin metal pans that can cause uneven browning. The 3-quart capacity is perfect for this recipe’s volume.

Saucepan for Roux

A heavy-bottomed 3-4 quart saucepan is crucial for the roux and sauce. I swear by my All-Clad stainless steel pot—it prevents scorching and gives me precise temperature control. The sloped sides make whisking easier.

Skillet for Mushrooms

Use a 12-inch skillet with a wide surface area to properly brown the mushrooms. My Lodge cast iron is my go-to; it retains heat beautifully and develops that perfect fond for extra flavor. Nonstick works too, but won’t build flavor the same way.

Whisk for Smooth Sauce

A sturdy balloon whisk is essential for lump-free sauce. I prefer the OXO Good Grips 11-inch—its comfortable handle and flexible wires make quick work of the roux. Avoid wooden spoons which can leave streaks in your sauce.

Honestly, this changed my sauce game forever. 💪

Measuring Tools

Accurate measurements matter for the sauce consistency. I use Pyrex glass measuring cups for liquids and OXO nested measuring cups for dry ingredients. A kitchen scale helps for the cheeses—4 oz of each type is perfect.

Mixing Bowls

Have a large mixing bowl ready for combining all ingredients. My stainless steel set from New Seasons Market nests neatly and cleans easily. The 5-quart size gives plenty of room to toss everything without spills.

Frequently Asked Questions