• Preheat oven to 400 degrees F.
• If you’re making homemade marinara sauce, see details below.
• To make the meatballs, in a large bowl, combine the ground chicken, breadcrumbs, ½ cup of the parmesan cheese, water, egg, garlic, onion powder, ½ teaspoon salt, and ¼ teaspoon black pepper.
• Mix well and shape the mixture into 12 meatballs (or smaller meatballs if you’re making the dish as an appetizer).
• Pour 1 cup of the marinara sauce into bottom of baking dish or cast-iron pan.
• Arrange the meatballs in the sauce. Pour over the remaining marinara sauce.
• Top the sauce with the mozzarella cheese and remaining ¼ cup of parmesan cheese.
• Bake, uncovered, for 25 to 30 minutes, until the internal temperature of the meatballs reaches 165 degrees F. If desired, place the pan under the broiler to brown the cheese.
• Top with basil, if using, and serve.

For the marinara sauce

• Heat the oil in a medium saucepan over medium heat. Add the onion and cook for 3 to 5 minutes, until soft.
• Add the garlic and oregano and cook for 30 seconds, until fragrant.
• Add the tomato puree, ½ teaspoon salt, and ¼ teaspoon black pepper and bring to a simmer. Reduce the heat to medium-low and simmer for 15 minutes.
• Season to taste with salt and pepper and use as directed.