Prepare Drum smoker for indirect cooking at 275 degrees F (135 degrees C). Add Pecan wood chunks to hot coals for smoke flavor.
Season Beef Cheek (6 pound) with Grande Gringo Mexican Seasoning (1/4 cup) and Killer Hogs Hot BBQ Rub (2 tablespoon).
Place Beef Cheeks on pit and smoke for 2 hours.
Remove beef cheeks from out and place in aluminum pan. Add Onion (1), Garlic (10 clove), Beef Stock (3 cup) and Mexican Style Hot Sauce (1/4 cup).
Insert wired probe thermometer into one of beef cheeks; cover pan with aluminum foil; return to pit until internal temperature reaches 210 degrees F (98 degrees C).
Rest the beef cheeks for at least 30 minutes and shred by hand. Drizzle with liquid from pan for moisture as needed.
To build tacos: warm Small Corn Tortilla (12) on grill or stove top. Place shredded beef cheek on tortilla and top with White Onion (1), Fresh Cilantro (1 bunch) and Cotija Cheese (1/2 cup). Dress with a drizzle of braising liquid and serve.