1️⃣ Preheat the oven: Preheat your oven to 350°F (175°C) and grease a 1.5-quart casserole dish with cooking spray or butter.

2️⃣ Cook the chicken: Place the chicken breasts in a saucepan and cover with water. Bring to a boil over high heat, then reduce to a simmer. Cook until no longer pink inside and juices run clear, about 15 minutes. Remove from water, let cool slightly, and cut into bite-sized pieces.

3️⃣ Cook the pasta: While the chicken is cooking, bring a large pot of lightly salted water to a boil. Cook the penne pasta according to package instructions until al dente, about 11 minutes. Drain and set aside.

4️⃣ Mix ingredients: In a large bowl, combine the cooked chicken, cooked pasta, Alfredo sauce, ¾ cup of mozzarella cheese, milk, onion powder, and garlic powder. Mix thoroughly to ensure the flavors are evenly distributed.

5️⃣ Assemble the casserole: Pour the mixture into the prepared casserole dish, spreading it evenly. Sprinkle the remaining ¾ cup of mozzarella cheese and the cheddar cheese over the top.

6️⃣ Bake: Place the casserole in the preheated oven and bake for 25 minutes, or until the cheese is fully melted and the dish is bubbly around the edges.

7️⃣ Serve: Let the casserole rest for 5 minutes before serving. Garnish with fresh parsley if desired and enjoy!