In a medium bowl, add the ground chicken, bread crumbs, Parmesan cheese, egg, 1 teaspoon of the minced garlic, parsley, and a generous pinch of salt and pepper. Mix everything well until combined. I often find that using my hands works best to ensure everything is well incorporated.
Using about 2 tablespoons of the mixture at a time, roll the mixture into balls and place them in a single layer on a baking sheet or plate. I like to use a medium scoop for uniformity, which usually yields around 20 meatballs, each about 1 ounce.
In a large oven-proof skillet, heat the olive oil over medium-high heat until shimmering. Once hot, carefully add the meatballs in a single layer. Cook them until they are browned all over, which takes about 2 minutes per side. If your skillet can't fit all the meatballs at once, feel free to do this in batches. Once browned, transfer them to a bowl, leaving the oil in the skillet.
Add the remaining minced garlic to the skillet and stir for about 30 seconds, or until fragrant. Be careful not to let it burn, as burnt garlic can turn bitter.
Next, add the crushed tomatoes, basil, oregano, and red pepper flakes (if using). Be cautious as the tomatoes might splatter when they hit the hot oil. Give everything a good stir and bring the sauce to a boil over medium-high heat.
Once boiling, return the meatballs to the skillet and gently stir to coat them with the sauce. Reduce the heat to medium-low, cover, and let them simmer until they are cooked through. This should take about 5 to 7 minutes. You can check that they are done when the internal temperature reaches 165 degrees.
After simmering, uncover the skillet and taste the sauce. Adjust the seasoning with more salt and pepper as needed. Sprinkle the top with mozzarella cheese, cover again, and let it cook for an additional 2 minutes or until the cheese is melted and bubbly.
Garnish with minced fresh parsley if desired, and prepare to serve this delicious creation!
