Preheat the oven to 400 degrees. Line a half sheet pan with parchment paper. Set aside.
In a mixing bowl, combine breadcrumbs, Parmesan cheese, egg, ¼ cup barbecue sauce, garlic, parsley, onion powder, salt, and pepper. Stir until the ingredients are evenly mixed.
Add the ground chicken. Using a fork, mix until the chicken and sauce are evenly incorporated. Use a 2 tablespoon cookie scoop to portion the mixture into meatballs. Place on the prepared pan.
Bake the meatballs for 15 minutes. Brush the meatballs with the remaining barbecue sauce. Bake until the meatballs reach an internal temperature of 165 degrees, approximately another 3-5 minutes.
Notes
Mixing: To avoid overmixing and creating tough meatballs, stir all of the ingredients except the ground meat together first. Then, using a fork, gently fold the ground meat with the other ingredients until just combined.Cooking: Use an instant-read thermometer to make sure the meatballs reach an internal temperature of 165 degrees.Storing: Store leftovers in the refrigerator in an airtight container for up to 3 days.Freezing: To freeze uncooked meatballs, form the meatballs and place them on a parchment-lined sheet pan. Freeze until firm, then transfer them to a freezer-safe zipper-top bag. Store for up to two months. Thaw in the refrigerator overnight. Bake according to the recipe's directions.To freeze cooked meatballs, cool the meatballs completely. Transfer them to an airtight freezer-safe container. Freeze for up to 2 months. Thaw in the refrigerator and reheat.