Ingredients: 1 2-1/2- to 3-lb. boneless beef chuck pot roast Salt and pepper 1/4 cup cooking oil 2 large onions, cut into 3/4-inch slices 3/4 cup water 1/4 cup red wine vinegar 1 tsp. dried thyme, crushed 1/4 tsp. salt 1 lb. potatoes 1 lb. carrots cut into 2-inch pieces 2 stalks celery, bias-sliced into 1-inch pieces 1/2 cup cold water 1/4 cup all-purpose flour Black pepper (optional)