In a large mixing bowl, combine the ground chicken, onion, breadcrumbs, Parmesan cheese, parsley, milk, eggs, minced garlic, lemon zest, salt, and pepper.
Shape the mixture into 2-tablespoon balls.
Heat the butter and oil in a large skillet over medium heat.
Add the meatballs and cook until all sides are browned, about 6-8 minutes.
Transfer to a paper towel-lined plate.
Deglaze the pan with white wine.
Mix in the chicken broth, lemon juice, and capers.
Return the meatballs to the pan and simmer for 5-8 minutes until the sauce reduces by half and the meatballs reach 165°F internally with an instant read thermometer.
Garnish with some extra chopped parsley and enjoy.
