Saucy Chuck Roast

1 (8 ounce) can tomato sauce
1/2 cup beef broth
1 medium onion, chopped
1 (3 to 4 pound) chuck roast
2 tablespoons vegetable oil
1/2 cup cider vinegar
1/4 cup catsup
2 teaspoon Worcestershire sauce
1 teaspoon prepared mustard
1 teaspoon paprika
1/8 teaspoon garlic powder

Combine first 3 ingredients in a shallow dish; add roast. Cover and marinate in refrigerator for 8 hours or overnight.

Remove roast from marinade, reserving marinade. Place roast in a Dutch oven. Combine marinade and remaining ingredients; pour over roast. Cover and bake at 350 degrees F for 2 1/2 to 3 hours or until roast is tender. Skim fat from sauce.

Serve sauce with roast.