In a Dutch oven, brown roast on both sides in oil. Season with sage, salt and pepper. Add beef broth. Cover and bake at 325 degrees f for 2 1/2 hours. Add potatoes, carrots and onions. Cover and bake 1 hour longer or until meat is tender and vegetables are cooked. Remove roast and vegetables to a serving platter and keep warm. Combine cornstarch and water; stir into pan juices. Cook until thickened and bubbly. DIABETIC EXCHANGE: One serving equals 3 lean meat, 1 starch, 1 vegetable; also 301 calories, 59mg sodium, 82mg cholesterol, 16gm carbohydrate, 27 gm protein, 14 gm fat.