Step 1:
Preheat your oven to 425°F.
Spray a 9×13 baking dish lightly with cooking spray or oil.

Step 2:
In a bowl, toss the diced chicken breasts with minced garlic, Italian seasoning, and oregano.
Let it sit for about 5 minutes to soak up all the flavors.

Step 3:
In the prepared baking dish, add the uncooked rigatoni pasta, marinara sauce, water, seasoned chicken, salt, and black pepper.

Step 4:
Stir everything together right inside the baking dish until well combined.

Step 5:
Cover the dish tightly with aluminum foil to trap the moisture.
Bake covered for 30 minutes.

Step 6:
After 30 minutes, remove the casserole from the oven and uncover it.
Give it a good stir — it’s normal if there’s still liquid, and the pasta may not be fully cooked yet.

Step 7:
Sprinkle the shredded mozzarella cheese evenly over the top.

Step 8:
Top with Panko breadcrumbs and grated Parmesan cheese for that perfect crunchy topping.

Step 9:
Return the dish to the oven and bake uncovered for another 10-15 minutes, until the cheese is golden and bubbling and the pasta is tender.

Step 10:
Garnish with freshly chopped basil before serving.