Step 1

Preheat oven to 425°F and move a rack to the upper third of the oven.

Step 2

Add 2 tablespoons butter to a large skillet and place over medium-high heat. Add mushrooms and cook until starting to soften, 2-3 minutes. Add sun-dried tomatoes and cook 2 minutes more. Add garlic and cook until fragrant, about 1 minute. Remove contents from skillet and set aside.

Step 3

Add remaining butter to skillet. Once melted, whisk in flour and cook, whisking constantly, for 2 minutes.

Step 4

Gradually whisk in milk, cream, and chicken broth. Cook, stirring occasionally, until mixture thickens, about 5 minutes. Stir in 1/2 cup Parmesan cheese, basil, red pepper flake, and season to taste with salt and pepper.

Step 5

Once cheese has melted, remove from heat and stir in sausage, tortellini, mushroom and tomato mixture, and spinach.

Step 6

Press tortellini down into liquid, top with remaining Parmesan and place in oven.

Step 7

Bake for 8 minutes, stir, and continue cooking until tortellini are tender, 3-5 minutes more. Enjoy!