In a small pan, heat the oil over medium heat and add the onion. Cook until softened then cool.
Combine milk and breadcrumbs, stirring to form a paste. Leave 5 minutes to allow crumbs to absorb the milk.
In a separate bowl, combine the ground beef, cooled cooked onion, breadcrumb mix, eggs, 1 tablespoon of Hardcore Carnivore Red, Worcestershire, 1 tablespoon of tomato paste and parsley. Work quickly to mix the ingredients thoroughly, but do not overwork the meat.
Carefully push the mix out onto a wire rack, and form a loaf shape. Cover with remaining seasoning. Place into the smoker and cook for 45 minutes.
In a bowl, combine remaining tomato paste, BBQ sauce and cider vinegar to make a glaze.
Brush meatloaf with glaze, then brush again every 30 minutes.
Cook the meatloaf until it reaches an internal temperature of 165f, about 3-4 hours.