Preheat your oven to 400°F (200°C).
In a large bowl, combine ground chicken, breadcrumbs, and Parmesan cheese.
Add chopped parsley, minced garlic, egg, salt, pepper, and Italian seasoning. Mix well.
Form the mixture into meatballs, about 1-1.5 inches in diameter.
Place the meatballs on a baking sheet lined with parchment paper.
Bake in the preheated oven for 20-25 minutes until golden brown.
While baking, heat marinara sauce in a saucepan on medium heat.
Once the meatballs are cooked, add them to the marinara sauce and simmer for 5 minutes.
Serve hot, garnished with additional parsley if desired.