Spicy Roast Beef

3 pound round tip roast or brisket trimmed of fat
1 to 2 tablespoons cracked black peppercorns
3 cloves garlic, minced
3 tablespoons balsamic vinegar
1/4 cup reduced sodium soy sauce
2 tablespoons Worcestershire sauce
2 teaspoons dry mustard

Rub cracked peppercorns and garlic onto roast. Put roast in crock pot. Make several shallow slits in top of roast.

In a small bowl, combine remaining ingredients and pour over meat. Cover; cook on LOW for 8 to 10 hours or on HIGH for 4 to 5 hours.