Lone Star Pot Roast

1 boneless beef chunk roast(3 to 3-1/2 pounds);2 T. cooking oil;1 can(14-1/2 ounces) tomatoes with liquid,cut up;1 can(4 ounces) chopped green chilies;2 T. taco seasoning mix;2t. beef bouillon granules;1t. sugar;1/4 cup cold water;3 T. all-purpose flour;I add a small chopped onion.In a dutch oven,brown roast & chopped onion in oil.Combine tomatoes,chilies,taco seasoning,bouillon and sugar;pour over the roast.Cover and simmer 2 to 2-1/2 hours or until meat is tender.Remove roast to a platter and keep warm.For gravy,pour 2 cups pan juices into a saucepan.Combine the cold water and flour;stir until smooth.Add to juices;cook and stir over high heat until thickened and bubbly,about 3 minutes.Slice roast.Serve with gravy.Yield 6-8 servings.