When the cheese on top starts bubbling, the edges of this casserole are already giving off a creamy, garlicky smell, but the middle still needs a little time. I built this creamy chicken and spinach tortellini casserole around that small timing difference: refrigerated tortellini goes into the oven just shy of al dente, so it finishes in the sauce instead of turning soft. The sauce clings to every fold, and the mozzarella melts into a golden blanket.
I make the sauce in the same Dutch oven I use to wilt the spinach, which keeps the steps tidy and gives the greens a chance to soften right in the creamy base. Shredded cooked chicken and the drained tortellini go in last, so they’re coated without getting knocked about. After a short rest, each scoop holds its shape, with tender pasta, chicken, spinach, and plenty of smooth sauce.
Kitchen Note
Softened cream cheese blends into the hot sauce much more smoothly than a cold block. If you still see little lumps, keep whisking until the sauce looks even before you add the spinach.
Save this creamy chicken and spinach tortellini casserole for a cozy dinner with tender pasta and a bubbling mozzarella top.
Why This Sauce Needs a Roux Before the Cream Cheese
Cream cheese brings richness, but it isn’t what gives this casserole its sturdy, spoon-coating sauce. Butter and flour make a roux first; once broth and milk are whisked in, that cooked flour thickens the liquid into a base that can cling to the tortellini, chicken, and spinach. The cream cheese and Parmesan then add their own creamy, savory character without having to carry the whole sauce.
That distinction matters in a baked pasta dish. Spinach releases moisture as it wilts, and the tortellini needs enough sauce around it to finish cooking in the oven. A sauce that looks thickened in the Dutch oven will still feel creamy after baking, rather than pooling at the bottom of the dish. Let the broth-and-milk mixture simmer until it visibly thickens before adding the cheeses; rushing that part leaves less body in the finished casserole.
The sauce shouldn’t be stiff or paste-like. It should fall from the whisk in a smooth, creamy ribbon and coat the back of a spoon. That gives the pasta room to absorb a little sauce while the casserole bakes without drying out.
The Ingredients That Keep the Sauce Creamy, Not Heavy
- Refrigerated cheese tortellini — Its filled shape gives each serving a tender center and catches sauce in the folds. Refrigerated tortellini also cooks quickly, so follow its package timing and stop just shy of al dente before it goes into the casserole.
- Whole milk and low-sodium chicken broth — Milk gives the sauce a fuller, rounder texture, while broth keeps it from tasting like a heavy cream sauce. Low-sodium broth leaves the salt level easier to control once the Parmesan is whisked in.
- Softened cream cheese — It adds body and a gentle tang. Let it soften before you start; it blends more readily into the hot sauce than a cold piece straight from the refrigerator.
- Grated Parmesan — Parmesan brings a salty, savory depth that’s different from the mild, stretchy mozzarella on top. Finely grated cheese melts into the sauce more easily than large shreds.
- Baby spinach — The tender leaves wilt quickly into the sauce and distribute through the casserole without needing to be chopped. Fresh leaves should look crisp and green, not wet or slimy.
- Shredded cooked chicken — Using cooked chicken keeps the filling ready to fold into the sauce and gives each bite a tender, substantial texture. Shred it into bite-size pieces so it’s easy to scoop with the tortellini.
- Mozzarella — Its mild flavor and melting quality make a soft, stretchy top layer. Shredded mozzarella spreads evenly over the casserole, so you get cheese across the whole surface rather than a few concentrated patches.
From Just-Shy Tortellini to a Bubbling Casserole
Grease the Dish and Par-Cook the Tortellini
Heat the oven to 375°F and grease a 9×13-inch baking dish with cooking spray. Bring a large pot of water to a boil and cook the refrigerated tortellini according to its package directions, stopping just shy of al dente. It should be tender at the edges but still have a little firmness in the center. Drain it well so excess water doesn’t thin the sauce.
Build the Creamy Sauce in the Dutch Oven
Melt the butter in a 5-quart Dutch oven over medium heat, then add the minced garlic and cook for 30 seconds. Whisk in the flour and cook for 1 minute; the mixture should look smooth and pale, not browned. Gradually whisk in the broth and milk, then bring everything to a simmer. Cook for 3 to 5 minutes, whisking, until the sauce thickens before you whisk in the cream cheese, Parmesan, salt, and pepper.
Wilt the Spinach and Coat the Filling
Stir the baby spinach into the sauce and give it 1 to 2 minutes to wilt. The leaves will shrink and turn soft while the sauce stays creamy around them. Fold in the shredded chicken and drained tortellini gently, just until everything is coated. If you stir too vigorously, the filled pasta can split and lose some of its shape.
Bake Until the Center Is Hot, Then Rest
Transfer the mixture to the prepared baking dish and spread the mozzarella evenly over the top. Bake for 20 to 25 minutes, until the sauce bubbles at the edges and the center reaches 165°F. The bubbling edges are a helpful visual cue, but check the middle too, since it takes longer to heat through. Let the casserole stand for 10 minutes before serving so the sauce settles around the pasta.
Three Practical Ways to Adapt This Tortellini Casserole
Use Spinach-and-Cheese Tortellini
Swap in refrigerated spinach-and-cheese tortellini for the cheese-filled kind. It gives the pasta a more pronounced spinach flavor while keeping the same filled, tender bite; cook it just shy of al dente before baking.
Make It Gluten-Free
Use gluten-free cheese tortellini, a gluten-free 1:1 flour blend in place of the all-purpose flour, and gluten-free chicken broth. The sauce may be a little less silky, but the roux still gives it body; cook the tortellini according to its package directions and drain it well.
Use Frozen Spinach Instead
Replace the baby spinach with 5 ounces of frozen chopped spinach, thawed and squeezed very dry. The result is more evenly dispersed and less leafy, but any water left in the spinach can loosen the sauce, so press it dry before stirring it in.
Storage and Reheating
- Refrigerator: Keep leftovers covered for 3 to 4 days. The tortellini softens a little as it sits in the sauce.
- Freezer: Freeze portions in airtight containers for up to 2 months. The sauce may separate slightly after thawing, and the pasta will be softer than when freshly baked.
- Reheating: Cover individual portions and warm them in the microwave until steaming hot throughout, checking that the center reaches 165°F. Reheat only until hot; prolonged heating can make the tortellini overly soft.
Questions That Come Up Before Baking
Creamy Chicken and Spinach Tortellini Casserole
Ingredients
Equipment
Method
- Heat the oven to 375°F.
- Grease a 9x13-inch baking dish with cooking spray.
- Cook the tortellini in a large pot of boiling water according to package directions until just shy of al dente, then drain.
- Melt the butter in a 5-quart Dutch oven over medium heat.
- Add the garlic and cook for 30 seconds.
- Whisk in the flour and cook for 1 minute.
- Gradually whisk in the broth and milk.
- Bring the mixture to a simmer.
- Cook for 3 to 5 minutes, whisking, until thickened.
- Whisk in the cream cheese, Parmesan, salt, and pepper until smooth.
- Stir the spinach into the sauce until wilted, about 1 to 2 minutes.
- Fold in the chicken and drained tortellini.
- Transfer the mixture to the prepared baking dish.
- Top evenly with the mozzarella.
- Bake for 20 to 25 minutes, until the sauce bubbles at the edges and the center reaches 165°F.
- Let stand for 10 minutes before serving.