Machaca Beef

1 1/2 lb. beef roast
1 large onion, sliced
4-oz can chopped gren chilies
2 beef bouillon cbes
1 1/2 tsp dry mustard
1/2 tsp garlic powder
1 tsp seasoning salt
1/2 tsp pepper
1 cup salsa

1Combine all ingredients except salsa in slow cooker. Add just enough water to cover
2 Put lid on and cook on low 10-12 hours or until beef is tender. Drain and reserve liquid
3.Shred beef using 2 forks to pull it apart
4 Combine beef, salsa, and enough of te reserved liqud to make of desired consistency
5. Use for burritos, chalupas, quesadillas or tacos