In a large pot, bring salted water to a boil. Cook the jumbo pasta shells according to package instructions until al dente, then drain and set aside.
In a large mixing bowl, combine the shredded chicken, ricotta cheese, half of the mozzarella cheese, Parmesan cheese, garlic powder, Italian seasoning, salt, and pepper. Mix well until all ingredients are fully combined.
Spread half of the Alfredo sauce evenly across the bottom of a 9x13 inch baking dish.
Stuff each cooked pasta shell with the chicken and cheese mixture and place the stuffed shells into the baking dish, open side up.
Once all shells are filled and placed in the dish, pour the remaining Alfredo sauce over the top, ensuring all shells are well coated.
Sprinkle the remaining mozzarella cheese evenly across the top of the dish.
Cover with aluminum foil and bake in the preheated oven for 25 minutes.
After 25 minutes, remove the foil and bake for an additional 10 minutes or until the cheese is bubbly and slightly golden.
Remove from the oven and let it cool slightly before garnishing with freshly chopped parsley.
Notes
Serve the stuffed shells on individual plates, drizzling extra Alfredo sauce over the top for a creamy touch and adding a sprig of parsley for color. Enjoy!