Preheat your oven to 350°F (175°C). Lightly oil a baking dish to prevent sticking and make cleanup easier.

Bring a large pot of salted water to a boil. Add spaghetti noodles and cook until al dente, following package instructions. Drain and set aside to cool slightly.

In a medium bowl, combine softened cream cheese, 2 cups of mozzarella cheese, Parmesan cheese, shredded chicken, half and half, oregano, garlic powder, onion powder, salt, and pepper. Mix until creamy and fully incorporated.

Spread half of the cooked spaghetti evenly into the greased baking dish. Top with half of the cheesy sauce mixture to create the first layer.

Add another layer of spaghetti noodles on top of the first layer. Spread the remaining cheesy sauce mixture evenly over the second layer of spaghetti.

Sprinkle the remaining 1 cup of grated mozzarella cheese evenly over the top.

Cover the baking dish with foil and bake for 30 minutes, or until heated through and bubbling.

Remove the foil and switch the oven to broil. Broil for 2–4 minutes until the cheese topping is golden brown and bubbly. Watch closely to avoid burning.