Ingredients:

1 1/2 cups reduced-sodium chicken broth
1/4 cup sherry vinegar
2 stalks celery, thinly sliced
1 large onion, chopped
1 large red bell pepper, seeded and chopped
3 cloves garlic, minced
1 tablespoon ground cumin
1 teaspoon salt
1/2 teaspoon freshly ground pepper
3 pounds flank steak, trimmed of fat, each steak cut into thirds
1/2 cup packed fresh cilantro leaves, chopped
1/2 cup chopped pickled jalapeno peppers
10 corn tortillas, heated (see Tip)

Method:

Combine broth, vinegar, celery, onion, bell pepper, garlic, cumin, salt and pepper in a 6-quart slow cooker. Add beef, submerging it by tucking the vegetables under, over and between the pieces.

Put the lid on and cook on low until the meat is fork-tender, about 8 hours.

Transfer the meat to a cutting board; let stand for 10 minutes. Shred the meat with 2 forks and return it to the slow cooker. Stir in cilantro. Garnish with jalapeno and serve warm tortillas on the side.