Balsamic Roast Beef

1 3-4 lb. boneless roast beef (chuck or round roast)
1 cup beef broth
1/2 cup balsamic vinegar
1 tablespoon Worcestershire sauce
1 tablespoon soy sauce
1 tablespoon honey
1/2 teaspoon red pepper flakes
4 cloves garlic, chopped

Place roast beef into the insert of a slow cooker. In a 2-cup measuring cup, mix together all remaining remaining ingredients. Pour over roast beef and cook 4 hours on high or 6-8 hours on low. Once roast beef has cooked, remove from slow cooker with tongs onto a serving dish. Break apart lightly with two forks and then ladle about 1/4 - 1/2 cup of gravy over the roast beef.
Store remaining gravy in an airtight container in the refrigerator.