Step 1

Set the oven rack to the middle position—Preheat the oven to 375°F (190ºC).

Step 2

In a large pot, bring water to a boil. Add the salt, stir to dissolve. Add in the spaghetti, cook according to package directions until al dente, about 10 minutes. Drain the noodles in a colander, and rinse with cool water for about 30 seconds to stop the cooking.

Step 3

Heat olive oil in a large skillet or dutch oven over medium-low heat. Add the onion, garlic, and 1 teaspoon Italian seasonings, sauté until onions are translucent, about 3 minutes.

Step 4

Add the marinara sauce, stir to combine. Cook until the sauce is hot, about 2 to 3 minutes. Turn off the heat and stir in the heavy cream. Season the sauce with more salt and pepper to taste.

Step 5

Add the drained spaghetti to the sauce, stir to combine. Add the shredded chicken and mix. Transfer the pasta to a 13x9-inch baking dish.

Step 6

Sprinkle the pasta with the shredded mozzarella and parmesan.

Step 7

Cover with foil and bake until the cheese melts and the pasta is hot, about 15 to 20 minutes. For a more browned surface, remove the foil, and broil the casserole until lightly browned, about 2 to 5 minutes.

Step 8

Garnish with chopped parsley, and serve immediately.