Preheat the oven to 350°F.
Bring a large pot of water (about 4 quarts) to a rolling boil. Add 1 tablespoon of table salt to season the water for the pasta.
Carefully add the pasta to the boiling water, stirring gently to prevent sticking. Follow the cooking time specified on the pasta package (usually around 9 minutes).
8 ounces jumbo pasta shells
Using a colander or strainer, drain the pasta to remove all the water. Set the drained jumbo pasta shells aside.
Meanwhile, prepare the chicken filling by combining the ingredients: chicken, ricotta cheese, parmesan cheese, mozzarella cheese, sour cream, Italian seasonings, black pepper, and salt. Mix until well combined.
1½ cups rotisserie chicken, 1 cup full fat ricotta cheese, ⅓ cup freshly grated parmesan cheese, ⅓ cup freshly grated mozzarella cheese, ⅓ cup sour cream, 1 teaspoon dried Italian seasoning, ½ teaspoon black pepper, ½ teaspoon kosher salt
Stuff the shells with the prepared chicken mixture and set them aside.
Heat a skillet over medium heat, melt the butter, and add minced garlic. Cook for a minute.
2 Tablespoons salted butter, 2 cloves garlic
Stir in the heavy cream and cook for 2 minutes.
1½ cups heavy cream
Add the parmesan cheese, Italian seasonings, salt, pepper, and crushed red pepper flakes. Let it simmer for 4-5 minutes until the sauce slightly thickens.
½ cup freshly grated parmesan cheese, ½ teaspoon dried Italian seasoning, ½ teaspoon salt, ½ teaspoon black pepper, ¼ teaspoon crushed red pepper flakes
Pour the sauce over the baking dish, arrange the stuffed pasta shells, and sprinkle mozzarella cheese on top.
Bake the stuffed shells for 18-20 minutes until the cheese has melted.
Garnish the pasta with parsley and red pepper flakes before serving.