You've probably noticed that most recipes for sauces, soups, and stews begin by asking you to cook one or more vegetables and occasionally a little meat in a small amount of fat. These basic mixtures go by different names in different cuisines, but they always play an important part in the character of a dish. A French mirepoix, an Italian soffritto, or a Portuguese refogado will each provide a foundation of flavor that will ultimately distinguish a dish from a similar one in another cuisine. It's helpful to know what goes into these basic mixtures and how and when to use them if you want to learn to improvise a sauce, soup, or stew without a recipe, or give a particular international twist to a simple dish.
Aromatic vegetables, herbs, and spices form classic flavor bases
In most European-influenced cuisines, classic flavor bases are made up of a mixture of three or four aromatic vegetables, sometimes herbs, and occasionally a small bit of meat. Asian cuisines often add freshly ground spices to their own combinations of aromatic vegetables and herbs.
Aromatic vegetables, which give off deep, well-rounded flavors and pleasing aromas when cooked, are the core of flavor bases. The classic French flavor base known as mirepoix (pronounced meer-pwah) is a combination of chopped onions, celery, and carrots made with twice as much onion as carrot and celery (see What size pieces should I cut?). The Italian soffritto (pronounced soh-FREE-toh) varies from region to region, and may be as simple as a chopped onion and a little garlic, or, like mirepoix, may be a mixture of vegetables that might include fennel. Italian cooks often like to use flavorful meats (especially pancetta or prosciutto) in the soffritto to give a hearty dish a deeper, richer flavor. A Catalan sofregit (soh-frah-ZHEET) starts with a slow sauté of onions in olive oil and is then enriched with tomatoes. A Spanish (or Castilian, to distinguish it from Catalan) sofrito, used to flavor classic rice dishes and rich braises, will usually include onions and garlic, and sometimes peppers, like its Portuguese equivalent, refogado (rah-foh-GAH-doh); tomatoes are often added.
Aromatic herbs and spices complete the flavor base. French cooks occasionally add a bay leaf or a little fresh thyme to their mirepoix. And it's not unusual to find a leaf or two of sage or a few sprigs of parsley in an Italian soffritto.
When you move on to the Eastern cuisines, you'll notice that cooks from non-European traditions work with a wider and more varied palette of aromatic vegetables and spices. A typical Indian base mixture for a curry may contain onion and garlic, hot chiles, and chopped ginger. And just before liquid is added, sophisticated hand-blended curry powders are added and quickly sautéed to release their fragrance. Indonesian cooks have an especially exotic base mixture—called bumbu—that includes shrimp paste, powdered galangal (an aromatic rhizome similar to ginger), and kemiri (or candlenut), an oily nut that gives a particularly unctuous texture to Indonesian stews. Thai cooks make one of several types of curry pastes for their flavor bases. The pastes are made by grinding together aromatics like shallots, lemongrass, chiles, and kaffir lime leaves.
What size pieces should I cut?
Fine dice for a quick-cooking sauce.
The size you cut the individual components of a flavor mixture depends on how long the mixture will cook and if it will be puréed. The French make a big deal out of demanding that a classic mirepoix be cut into very tiny dice (called brunoise)—a handy way of torturing beginning culinary students. But there's actually a sound reason for chopping mirepoix into small pieces for a quick-cooking dish: the smaller pieces will release their flavor more quickly during the short cooking time. On the other hand, mirepoix for a pot of long-simmering stock can consist of very large pieces of vegetables—onions cut in half, whole celery ribs, and carrots in chunks.