Preheat your oven to 375°F (190°C).
Cook the pasta according to package instructions until al dente, then drain and set aside.
In a large skillet, heat olive oil over medium heat. Add the cubed chicken and cook until browned and cooked through.
Add the minced garlic and sliced zucchini to the skillet and sauté for 2-3 minutes.
Stir in the marinara sauce and Italian seasoning. Season with salt and pepper.
Combine the cooked pasta, chicken mixture, and half of the shredded mozzarella cheese in a large mixing bowl.
Transfer the mixture to a greased baking dish and top with the remaining mozzarella cheese.
Bake in the preheated oven for 20-25 minutes, or until the cheese is bubbly and golden brown.