Bring a pot of heavily salted water to a boil. Cook the tortellini according to package instructions. Drain, and set aside.
1 9 oz pkg refrigerated cheese tortellini
While waiting for the water to boil, in a large skillet over medium heat, cook the sliced sausages until cooked and nicely browned. Transfer to a plate or bowl.
1 19 oz pkg Italian sausages
Add the butter to the drippings, stirring to melt. Stir in the garlic, Italian seasoning, and red pepper flakes until fragrant, about a minute.
2 tbsp butter, 4 tsp minced garlic, 1/2 tsp zesty Italian dressing mix, 1/4 tsp crushed red pepper flakes
Stir in the flour, constantly whisking until slightly browned and the flour taste has cooked out, about a minute or so. A little at a time, whisking constantly-add in the milk and cream, waiting each time until the roux has reformed before adding some more, until it's all come together.
2 tbsp flour, 3/4 cup milk, 3/4 cup cream
Let the mixture simmer, whisking occasionally, until thickened, about 3-5 minutes.
Remove the skillet from heat and stir in the cheese. When the cheese has melted, add the sausage & pasta to the skillet. Stir until everything's evenly combined. Salt & pepper, to taste.
2 oz cream cheese, 1/4 cup shredded Parmesan cheese, salt & pepper
Serve immediately.