Preheat the air fryer. Set it to 390°F (200°C) for 3–5 minutes. A hot basket helps the meatballs brown nicely.

Mix the breadcrumbs and liquid. In a large bowl, combine breadcrumbs with a splash of milk or water. Let it sit 1–2 minutes to hydrate. This keeps the meatballs juicy.

Build the mixture. Add ground chicken, egg, Parmesan, garlic, onion, parsley or Italian seasoning, salt, and pepper. If using add-ins like red pepper flakes or lemon zest, mix them in now.

Combine gently. Use a fork or your hands to mix until just combined. Do not overmix or the meatballs can turn dense.

Form meatballs. Lightly oil your hands and roll the mixture into 1 to 1.5-inch balls. Aim for uniform size for even cooking. You should get about 18–22 meatballs, depending on size.

Prep the basket. Spray the air fryer basket lightly with olive oil to prevent sticking.

Arrange and mist. Place meatballs in a single layer with a little space between each. Lightly mist the tops with oil for better browning. Work in batches if needed—don’t overcrowd.

Air fry. Cook at 390°F (200°C) for 9–12 minutes, shaking the basket or turning the meatballs halfway. They’re done when the centers reach 165°F (74°C) and the outsides are lightly golden.

Rest and serve. Let meatballs rest 2 minutes to lock in juices. Serve with warm marinara, pesto, buffalo sauce, or a lemony yogurt dip.