In addition to using a richly flavored turkey or chicken stock or broth to make gravy, consider adding other flavor enhancers.
• Wine: Use white instead of red, because the latter can turn the gravy an odd purple-gray color. Use no more than 1/4 cup of wine for every cup of stock or broth.
• Roasted garlic: For every cup of gravy, whisk in 2 to 3 tablespoons of roasted garlic puree. (To roast garlic, lop off the top of a head of garlic so that its cloves are exposed a bit. Drizzle with olive oil and wrap tightly in aluminum foil, then roast for about 40 minutes in a 400-degree oven. Squeeze the cloves into a small bowl and mash to form a puree.)
• Caramelized onions or shallots: Chop onions or shallots and cook slowly (for at least 30 minutes) in butter until very tender and dark golden brown. Add about 1/4 cup for every cup of gravy.
• Liquor: Sounds like a good idea, and it is. But don’t overdo it. Add no more than 2 tablespoons of bourbon, cognac, brandy, port wine, Madeira or sherry for every cup of gravy.
• Chili peppers: Use a dedicated spice grinder to finely process dried ancho, chipotle or habanero peppers, depending on the heat level you like. Do not use store-bought chili powder, which might contain other spices. Add the freshly ground pepper to the gravy gradually, by the quarter-teaspoonful, to taste.