Set Sun Oven out to preheat.
Place a toaster oven rack in a large roasting pan. Fold a long piece of aluminum foil in half lengthwise and place it over the rack with the ends extending out on both sides. Spray the foil with cooking spray.
In a large mixing bowl use your hands to combine all the ingredients. Shape the mixture into a oval loaf and place it on the foil. Insert a probe thermometer into the center of the loaf (optional). Cover the roasting pan and cook the meatloaf in the Sun Oven until it reaches an internal temperature of 160, 2 1/2 to 3 hours. Let rest 5 minutes before using the foil to lift the loaf out of the pan and onto a platter.