Shredded Beef Tacos

1 pound boneless beef chuck
1 cup water
6 peppercorns
1 small onion
Salt
1 garlic clove
1/4 teaspoon salt
1 tablespoon vegetable oil
1/2 medium onion, chopped
1 California chile or 1 poblano chile, roasted and peeled,
    or 1 canned whole green chile
2 small tomatoes, peeled and chopped
1/4 teaspoon ground cumin
Freshly ground pepper
6 to 8 corn tortillas

Garnish:
Salsa
1 avocado
Juice of 1/2 lime
Salt
1 onion, chopped
Cilantro leaves, chopped

Place meat in a large saucepan. Add water, peppercorns, onion and salt to taste. Bring to a boil; reduce heat. Cover and simmer until meat is very tender, about 1 1/2 hours. Cool meat in broth. Drain, reserving 1/3 cup broth. Shred meat with 2 forks. Set aside.

Mash garlic with 1/4 teaspoon salt to make a paste.

Heat oil in a large skillet. Add chopped onion and garlic paste. Cook until onion is tender. Cut chile into short strips. Add chile strips and tomatoes to cooked onion. Cook 3 to 4 minutes. Add meat, cumin and freshly ground pepper to taste. Cook and stir until meat is heated through. Stir in reserved broth. Taste and add salt if needed. Keep warm.

Heat oven to 350 degrees F.

Wrap tortillas in foil and place in oven until softened, about 15 minutes.

Prepare salsa if making fresh. Mash avocado in a small bowl. Stir in lime juice and salt to taste. Beat until smooth. Place avocado mixture, onion, cilantro and salsa in separate bowls and set aside.

For each taco, place spoonful of shredded beef on a warm tortilla. Top with avocado mixture, onion, cilantro and salsa to taste. Fold tortilla around filling. Serve immediately.