Place the beef into your crockpot.
In a small bowl stir together taco seasoning, red wine vinegar, and green chilies.
Spoon sauce over beef.
Cook on low until the meat falls apart easily with a fork (8-10 hours)
Take beef out and shred with a fork
Serve with taco shells or tortillas, sour cream, cheese, lettuce, tomatoes. salsa, and guacamole.