Thanksgiving gravy is traditionally made from roast turkey drippings. Use this recipe when barbecuing a turkey because there are no drippings.
In a medium saucepan set over low heat, warm chicken stock. Meanwhile, place butter in a small saucepan over medium heat. Add shallots, and saute until translucent, about 3 minutes. Add flour, and stir constantly with a wooden spoon, scraping cooked-on bits from bottom of pan, until mixture becomes light brown but does not burn.
Slowly add warm chicken stock to the saucepan, and stir constantly until mixture thickens, 8 to 10 minutes. Add tomatoes and tomato juice, sage, marjoram, salt, and pepper. Reduce to a gentle simmer, and cook until thickened, about 25 minutes more. Serve immediately.