• Preheat the oven to 350° and spray a 9 x 13 deep baking dish with non-stick cooking spray. Set aside.
• Cook pasta per package directions for al dente.

For the Meat Sauce

• In a large skillet, or frying pan, over medium high heat, cook Italian sausage and onions until sausage is no longer pink and onions are tender. Drain and return to pan.
• Sprinkle with seasonings, stir.
• Pour tomato sauce and tomato paste into the meat mixture. Stir to combine, cover and let simmer, stirring occasionally.

For the Creamy White Sauce

• In a medium saucepan, over medium heat, melt butter and then stir in flour.
• Pour heavy whipping cream into the pan and stir until combined.
• Add Parmesan cheese, stir until melted and add salt and pepper.
• Add pasta water to cheese sauce, stir.
• Add cooked tortellini to cheese sauce, stir to combine.
• Pour pasta and cheese sauce into the prepared baking dish followed by the sausage mixture on top.
• Sprinkle with mozzarella cheese and bake uncovered for 20 minutes or until the cheese is hot and bubbly.