In a large bowl, combine the ground chicken, eggs, breadcrumbs, Parmesan, Italian seasoning salt, and pepper. Mix gently until combined. Don’t over mix or squish around the meat too much or you’ll end up with tough, dense meatballs.
Shape the meatball mixture into small balls, about 2 tbsp, and then press a hole in the center with your thumb. Place a piece of mozzarella into each. Reseal the meatball mixture around the mozzarella, making sure to cover it completely. You don’t want to see any of the cheese or it will ooze out when cooking.
Once all of the meatballs have been stuffed, roll them one at a time in the panko/cheese mix to coat. Press the crumbs into the meatballs a bit, while still maintaining their meatball shape. Place meatballs on a small sheet pan or plate and chill in the fridge for about 15-30 minutes before frying.
Preheat oven to 350° Place an oven-safe skillet (I prefer my 12 inch cast iron) over medium heat with 2 tablespoons of olive oil. Brown Meatballs 5-6 minutes, rolling over a few times to brown as much of the outside as you can. You want the exterior to be a nice golden brown. The meatballs won't be done at this point, but will continue cooking in the oven. You’ll probably need to do this in two batches, wiping out the pan between batches and adding new oil. Remove finished meatballs to a plate and continue with second batch. When done, wipe out the pan again.
Pour the marinara into the skillet and then nestle the meatballs into the sauce. Place into the oven and bake for 15 minutes. Remove from oven, sprinkle shredded mozzarella cheese around the meatballs and place back into the oven to bake for an additional 5-6 minutes, or until the cheese has melted. If desired, broil for a few minutes to brown the cheese a bit.
Garnish with grated parm and fresh basil. Serve with garlic bread, your favorite pasta, or use slider buns to make mini chicken parm sandwiches.