Barbecued Chuck Roast

I posted this recipe in answer to a message board request for "something different to do with a chuck roast". It is a recipe that I used to make quite often, but I haven't made it in a few years (another of those "forgotten recipes").

• Ready In: 3 hrs 35 mins
• Serves: 6

Ingredients

• 1 (3 lb)  chuck roast (1 1/2 to 2 inches thick)
• 1  teaspoon msg or 1  teaspoon  meat tenderizer
• 1⁄3 cup wine vinegar
• 1⁄4 cup ketchup
• 2  tablespoons  oil
• 2  tablespoons soy sauce
• 1  tablespoon Worcestershire sauce
• 1  teaspoon prepared mustard
• 1  teaspoon salt
• 1⁄4 teaspoon pepper
• 1⁄4 teaspoon garlic powder

Directions

1. Sprinkle meat on both sides with tenderizer (or MSG).
2. Place roast in a shallow bakng dish (or zip lock bag).
3. Thoroughly combine remaining ingredients.
4. Pour over roast and marinate 2-3 hours, turning twice.
5. Place marinated meat on grill, about 6 inches from heat.
6. Turn roast and baste with marinade every 10 to 15 minutes.
7. Grill over medium coals about 35-45 minutes for meduim-rare.