Preheat your air fryer: Begin by preheating your air fryer to 375°F (190°C/Gas Mark 5). Ensure it reaches the desired temperature to ensure accurate cooking times.
Prepare the aluminum foil: Take a sheet of aluminum foil slightly larger than your meatloaf. Lightly coat it with non-stick cooking spray. This will allow you to fold up the edges, creating a "tray" for your meatloaf.
Measure Out ingredients: In a large mixing bowl, combine the following ingredients - 2 pounds (907.18 grams) of ground beef, 2 large eggs, 1 small diced onion, ¼ cup (59 milliliters) of milk, 1 cup (60 grams) of Panko breadcrumbs, 2 tablespoons (29.5 milliliters) of Worcestershire sauce, ½ cup (117.5 grams) of ketchup, 1 tablespoon (8 grams) of minced garlic, 1 tablespoon (5 grams) of Italian seasoning, 1 teaspoon (2 grams) of ground mustard, 1 teaspoon (6 grams) each of salt and pepper, and ½ teaspoon (1 gram) of smoked paprika. Remember to set aside ½ cup of ketchup for later use in step 5.
Mix the meatloaf ingredients: Thoroughly combine all the ingredients in the mixing bowl. You can use your clean hands to ensure the mixture is well incorporated.
Form Your Meatloaf: Create an even rectangular shape for your meatloaf, approximately 2-3 inches thick. Place the meatloaf on the prepared aluminum foil with the edges turned up to form a tray-like shape.
Transfer And Cook: Put the meatloaf into the air fryer and cook it at 375°F (190°C/Gas Mark 5) for 30 minutes.
Apply ketchup topping: Open the air fryer and evenly spread the reserved ½ cup (117.5 grams) of ketchup over the entire top of the meatloaf.
Finish cooking the meatloaf: Continue cooking for an additional 10 minutes at 375°F (190°C/Gas Mark 5). The internal temperature of the meatloaf should reach 160-165°F (71-74°C). If it hasn't reached this temperature, cover the meatloaf with aluminum foil and cook for a few more minutes until it's done.
Drain and serve: Carefully remove the meatloaf from the air fryer. You can tilt the air fryer basket to drain any excess fat and liquid. Let the meatloaf rest for a few minutes to cool slightly before transferring it to a serving plate and slicing. If desired, garnish with fresh chopped parsley.