Preheat the oven to 350°F and set aside a large oven-safe skillet.
In a large bowl, combine the Parmesan, breadcrumbs, eggs, tomato paste, Italian seasoning, parsley, garlic powder, kosher salt, and black pepper. Use a fork to mix these together well.
3/4 cup grated Parmesan cheese, 1/2 cup Panko breadcrumbs, 2 large eggs, 3 Tablespoons tomato paste, 2 teaspoons Italian seasoning, 1 teaspoon dried parsley, 1 teaspoon garlic powder, 1 teaspoon kosher salt, 1/4 teaspoon black pepper
Add ground chicken to the bowl. Continue using the fork to very gently pull the breadcrumb mixture through the meat, until it is pretty even. Try not to overwork.
2 pounds ground chicken
Scoop the mixture out into medium-large meatballs, roughly 2-3 Tablespoons each. Using your hands, open each meatball and press a ball of mozzarella inside, then shape and pinch the meat around it so the cheese is completely covered. Set prepared meatballs aside on a plate.
8 ounces mozzarella pearls or pieces
Warm the olive oil in your skillet over medium-high heat. Add the meatballs and cook for 5-6 minutes, turning frequently, until they are evenly browned. Work in batches as needed to avoid over-crowding, setting browned meatballs aside on a paper-towel lined plate.
1-2 Tablespoons extra virgin olive oil
When all the meatballs are browned, gently wipe out the skillet, then pour in the marinara. Scrape the bottom of the pan to loosen any browned bits.
2 cups marinara sauce
Nestle meatballs back into the sauce, then transfer the pan straight into the hot oven.
Bake for 15-18 minutes, until the sauce is bubbling and meatballs are cooked through. If desired, sprinkle with additional mozzarella during the last few minutes of baking. Serve with additional cheese, herbs, and pasta, as desired.
pasta, extra Parmesan, fresh herbs, etc.