Preheat your oven to 350°F (176°C). Line a rimmed baking sheet with aluminum foil, and lightly spray the surface with nonstick cooking oil. Set the prepared baking sheet aside.

In a small mixing bowl, combine the ketchup and packed light brown sugar. Stir thoroughly until the mixture is smooth and the sugar is fully incorporated. Set this glaze aside for use later.

In a large mixing bowl, beat the eggs until well blended. Add the Italian breadcrumbs (or Panko for extra crunch), whole milk, grated Parmesan cheese, finely diced onion, 1/4 cup ketchup, Worcestershire sauce, dried parsley, garlic powder, fine sea salt, and ground black pepper. Mix these ingredients until evenly incorporated. This forms the wet base for your meatloaf.

Add the ground chicken to the bowl with the wet mixture. Gently break up the meat and use your hands to mix everything together just until combined—be careful not to overwork the meat so your meatloaf stays tender. Transfer the mixture to the center of the prepared baking sheet. Shape it into a loaf, pressing the meat together tightly and making sure the loaf is of even height and thickness for even cooking. I always make sure not to overmix the chicken, as it helps keep the meatloaf juicy and tender.

Spoon the prepared glaze (from Step 2) evenly over the top and sides of the shaped meatloaf. Place the baking sheet in the preheated oven and bake for 50 minutes. After baking, turn the broiler on and broil the meatloaf for about 3 minutes to caramelize the glaze. The meatloaf is done when an instant read thermometer inserted in the thickest part reads 165°F.

Let the meatloaf rest for 10 minutes before transferring it to a serving tray. Slice into 1- to 1 1/4-inch thick pieces and garnish with fresh chopped parsley, if desired. For extra color and fresh flavor, I always recommend the parsley garnish.