By Harold McGee
The most complex and sophisticated puree sauces are made in Asia and Mexico. The sauce or “gravy” for many Indian and Thai dishes begins with finely ground plant tissues—onions, ginger, garlic in northern India, coconut in southern India and in Thailand—and a number of different spices and herbs. These ingredients are then fried in hot oil until much of the moisture has boiled off, and the plant solids are sufficiently concentrated that the sauce clings to itself and the oil separates. The frying also cooks the sauce, eliminating raw flavors and developing new ones. The sauce is then slightly thinned with some water, and the main ingredient cooked in it. Mexican mole sauces are prepared in much the same way, except that the foundation ingredient is usually rehydrated dried chillis; pumpkin and other seeds are another major element. Thanks to the high pectin content of the chillis, moles have a more suave, finer consistency than the Asian purees. But both are marvels of mouth-filling pleasure.