Leave it to creative French cooks to turn the humblest of ingredients, onions and bread, into a world famous culinary work of art. Onion soup started off as an inexpensive dish that became popular as an early-morning breakfast among revelers who had stayed out late and had a bit too much to drink; it was basically a cure for hangovers. When we lived in Paris, my husband and I enjoyed it as a late-night supper after an evening walk. The casual Parisian eateries where it was served became renowned not only for their soup, but for their funny names, like "au chien qui fume" - the dog who smokes, which was founded in 1740 and has a dog smoking a pipe as its logo. In its most modest form, the homey soup is composed of onions cooked in broth, then topped with stale bread and a sprinkling of cheese. Eventually chefs turned it into a concoction of onions stewed in butter for nearly an hour, then simmered at length in a rich stock made from roasted veal bones that had cooked for hours in water with aromatic vegetables. Finally the deep-brown soup was topped with toasted country bread and Gruyere cheese and browned in the oven to acquire a delectable bubbling crust. Some chefs made the soup even more luscious by enriching it with port wine and egg yolks. It turned into a delicious meal-in-a-dish and became the most celebrated soup of France. Onion soup is fun to prepare and serve at home too. Lydie Marshall, author of Soup of the Day, makes hers from a combination of onions, leeks and shallots. For the topping, she bakes her own sourdough bread, beginning with a starter that requires three days to ferment. To make a simpler style of onion soup, she uses the same basic elements - onions, bread and cheese. She layers sliced bread and cheese in a tureen and pours the boiling soup of onions simmered in broth on top. The result is a thick, satisfying soup. Deborah Madison, who wrote Vegetable Soups from Deborah Madison's Kitchen, noted that the first step of making onion soup - cooking onions slowly in oil or butter until they soften before adding any liquid - is the best way to begin making most vegetable soups. "It's important not to rush this step; the longer you give it, the better your soup will be. Browning onions contributes hearty flavor and rich color to the soup." Her onion soups depart from the classic and do not need meat broth. For her red wine onion soup, she uses red onions and flavors the soup with chopped tomatoes. She makes olive lemon onion soup with chopped black Nicoise olives and strips of lemon peel, as well as white wine, thyme and bay leaves. She then bakes the soup with toasted sourdough bread, grated Parmesan and goat cheese, and gets a cross between a soup and a casserole. Not many people are familiar with the second basic type of French onion soup, which is equally scrumptious. This version is creamy. According to Auguste Escoffier, author of Guide Culinaire devoted to classic French cooking, it is made of onions sauteed in butter, then sprinkled with flour and cooked in broth and milk. You mix part of the onions with thick cream sauce and spread it on dried baguette slices to make croutons, which are then sprinkled with grated cheese, browned in the oven and served with the soup. The cooks of the Moosewood Collective, who wrote Moosewood Restaurant Daily Special, stir cheese directly into the soup instead of sprinkling it on croutons. Their creamy cheesy onion soup begins like Escoffier's version and is flavored with white wine, Dijon mustard and plenty of grated fontina cheese. Onion soup doesn't necessarily contain cheese. Barbara Kafka, author of Soup - a Way of Life, created an easy-to-make spicy onion soup by adding curry powder to butter-cooked onions, simmering them in broth and finishing the soup with a squeeze of lime juice. To complete her luxurious soup, she stirs in a lavish dose of heavy cream. If you wanted to make such a soup parve, you could saute the onions in oil, and omit the cream or substitute rice milk or soy milk. The soup will still taste wonderfully rich as long as you use a generous proportion of onions and saute them with patience so they turn caramel-brown. Use prepared vegetable broth or vegetable cooking liquid as the liquid for preparing this soup. Part of the onions from the soup are used as a topping for the accompanying croutons. 2 Tbsp. butter or vegetable oil or 1 Tbsp. butter and 1 Tbsp. oil 3 large onions, halved and sliced thin 1 large garlic clove, minced 2 Tbsp. all-purpose flour 13â„4 to 2 cups vegetable broth 2 sprigs fresh thyme 1 bay leaf About 21â„2 cups milk 8 to 12 slices baguette, lightly toasted 2 to 3 Tbsp. grated Parmesan or 4 to 6 Tbsp. grated Swiss cheese Salt and white pepper Freshly grated nutmeg 1 Tbsp. minced parsley Heat butter in a heavy medium saucepan. Add onions and cook over medium heat, stirring often, about 10 minutes or until soft but not brown. If onions begin to brown, cover pan after 5 minutes of cooking so that the steam will help inhibit browning, but continue stirring often. Add garlic to pan of onions and cook a few seconds. Sprinkle flour over mixture and cook over low heat, stirring, for 1 minute. Gradually add broth, stirring. Bring to a simmer. Add thyme sprigs and bay leaf. Cook for 10 minutes or until onions are fairly tender. Pour in 2 cups milk, stirring, and return to a simmer. Cook uncovered over low heat, stirring often, for 10 minutes. Discard thyme and bay leaf. With a slotted spoon, remove about 1â„3 of the onions. Puree in a food processor. Return puree to a small saucepan and cook until thick. Spread a little on each piece of toast, and sprinkle with cheese; if any puree remains, return it to pan of soup. Brown cheese toasts lightly in the broiler. If soup is too thick, stir in a little more milk. Season to taste with salt, white pepper and nutmeg. Serve hot, sprinkled with parsley and accompanied by the onion-cheese toasts. Makes 4 to 6 servings. Faye Levy is the author of Fresh from France: Vegetable Creations.