The Gotchas

• When you begin cooking vegan soups, a few familiar ingredients are obviously out of the question. Those include meat- or fish-based stocks and concentrates, as well as eggs, dairy products and savory flavorings such as fish sauce. Other non-vegan ingredients are less obvious. For example, Worcestershire sauce's flavor-enhancing tang is based on anchovies and tamarind. Unless your bottle specifically says it's a vegetarian variety, it isn't. If you're making one of the relatively small number of soups that requires sweetening, honey -- considered an animal product by vegans -- is out. Many vegans also shun refined sugar, which is often filtered through charcoal made from animal bones. Evaporated cane syrup and other "raw" sugars, or maple syrup, are better alternatives.

A Good Broth

• Making a flavorful broth without those aids is not difficult, though it might require a bit of trial and error. Many vegan-friendly soups begin with onions, celery and carrots, the classic combination known as "mirepoix." This creates a balanced base flavor, which can then be enhanced by the addition of peppercorns, parsley stems, thyme, bay leaves, mushrooms, leeks, shallots and many other herbs, spices or aromatic vegetables. Some soups include enough of these ingredients to require no advance preparation. Others are better if you prepare a vegetable broth ahead of time, and use that as the base of the soup. If you're in a hurry, tomato juice -- either from a can, or from fresh tomatoes -- is a useful substitute.

Thick, Rich Soups

• You can also make thick, rich, hearty cold-weather soups that are perfectly vegan-friendly. Most vegetables can be simmered in broth and then pureed to make a soup base. Winter squashes and root vegetables such as carrots are especially good at this, but broccoli, cauliflower and many others are also suitable. Some benefit from a starchy thickener to improve their texture. If you miss cream soups, you have a wealth of vegan alternatives to choose from. Coconut milk and coconut cream -- but not the "creamed coconut" used in mixed drinks -- make excellent cream soups, if their mild tropical flavor is suited to the soup's flavor profile. Alternatively, substitute nut milk or soy milk for dairy milk and cream. Ground cashews, or stirred-in nut butters, make an especially rich soup.

A Few Cheats

• At times, your experiments don't work out as well as you'd hoped, but a few cheats are available to help. Dried mushrooms or kombu, a seaweed, give the broth a deeper, richer flavor and make it more savory. You can stir miso, the fermented soybean paste, into the soup at the last moment to give it body and rich, savory notes. Use soy sauce in dark soups to add umami to the finished dish, or vegan-friendly liquid amino acids. Many soups, especially pureed soups and faux-cream soups, benefit from a splash of bright acidity at the end. Stir in a few drops of lemon juice or good-quality vinegar, just before serving the soup.