Preheat a smoker to 225°F.
In a large bowl, combine the ground beef, sausage, rolled oats, milk, egg, grated onion, ground cumin, and smoked paprika. Using your hands, massage the wet ingredients into the ground meat and mix until well incorporated.
Pack the meatloaf tightly and form into a loaf on a piece of aluminum foil or parchment paper.
Prepare the glaze by combining the ketchup, mustard, brown sugar, apple cider vinegar, and Worcestershire sauce in a small bowl.
Smoke the meatloaf for 1 hour. Add the glaze and continue cooking for 1 to 2 hours, until the internal temperature reaches 160°F.
