Preheat oven to 375°F and lightly grease a loaf pan or line with parchment paper.
In a large mixing bowl, combine ground chicken, breadcrumbs, Parmesan, garlic, egg, milk, salt, pepper, and herbs.
Mix gently until just combined to avoid a dense texture.
Transfer the mixture to the loaf pan and shape into a loaf.
Brush the top with olive oil and bake for 45–50 minutes, until the internal temperature reaches 165°F.
In the last 10 minutes, brush with garlic butter glaze and sprinkle mozzarella if desired.
Let rest 5–10 minutes before slicing and serving.