1. Liberally coat all sides of the beef chuck with all-purpose rub.
2. Preheat smoker to 225F and place a fist-sized chunk of your favorite smoking wood. Smoke beef indirect, until it hits an internal temp of 165F.
3. Remove beef from the smoker and add it into a foil pan. Pour over Birria sauce and water, before placing back on the smoker until the beef hits an internal temp of 203F.
4. Once the internal temperature is met, remove from the heat and allow the beef to rest for 30 minutes, tented loosely in foil.
5. After resting, pull meat into bite-sized chunks and separate from the Birria sauce.
6. Dunk both sides of each tortilla in the Birria sauce before placing on the cast iron skillet to sear tortillas-about 1 minute on each side.
7. Make Salsa Verde before finely dicing onions and cilantro.
8. Serve tacos with a generous serving of the pulled beef, a sprinkle of onions, cilantro, and a heaped tablespoon of Salsa Verde.