In a large saucepot, brown meat in hot vegetable oil, over high heat.
Add water, Worcestershire sauce, garlic, onion, paprika. Season with salt and pepper.
Cover and simmer for 1 1/2 hours. Remove garlic clove. Add carrots and celery. Cover and cook 30-40 minutes longer.
To thicken gravy, remove 2 cups hot liquid. Using a separate bowl, combine 1/4 cup water and cornstarch until smooth. Mix with a little hot liquid and return mixture to the pot. Stir and cook until bubbly.