Preheat your oven to 375°F (190°C) and line a baking tray with parchment paper.
In a mixing bowl, combine the ground chicken, breadcrumbs, Parmesan cheese, chopped parsley, minced garlic, egg, dried oregano, salt, and black pepper. Mix well until all ingredients are fully incorporated.
Using your hands, shape the mixture into 1.5-inch meatballs and place them on the prepared baking tray.
Bake in the preheated oven for 20 minutes or until cooked through and lightly browned on the outside.
While the meatballs are baking, heat the marinara sauce in a saucepan over medium heat until warmed.
Once cooked, remove the meatballs from the oven and carefully place them in the saucepan with the marinara sauce. Stir gently to coat the meatballs in the sauce.
Sprinkle the shredded mozzarella cheese over the meatballs and cover the saucepan for about 5 minutes, allowing the cheese to melt.
Serve the chicken meatballs supreme warm, garnished with fresh basil leaves for a burst of color and flavor.