The thing that defines salsa verde is the tomatillo. Not green chile, not herbs: the small, husked, tart green fruit that gives this salsa its color, its body, and its bright, acidic backbone. That is the clean line between it and the dried-chile red. Where salsa roja is deep, roasted, and earthy, salsa verde is sharp, fresh, and vegetal, a tangy lift built on tomatillo with serrano or jalapeño for heat and cilantro for an herbal top note. Its structural job on a taco, a torta, chilaquiles, or enchiladas verdes is to cut, not to deepen: the tomatillo acid slices through fat, the chile adds a clean green burn, and the whole thing reads cool and bright against rich, heavy components.
The make forks at one decision: raw or cooked tomatillos, and that choice changes the salsa completely. Raw, salsa verde cruda, the husked tomatillos go into the blender uncooked with chile, onion, garlic, and cilantro, giving a pale, grassy, aggressively tart and slightly foamy salsa with maximum brightness and bite. Cooked, the tomatillos are boiled or charred on a comal first, which mellows the acid, deepens the color to a duller olive, and rounds the flavor into something softer and savory. Asada, the roasted version, adds a faint smoky char. Either way, balance is the test. Good salsa verde is bright but not sour to the point of puckering, with the chile and salt holding the tomatillo's edge in check and the cilantro present but not soapy. Poor versions tip too far: underripe tomatillos or no salt leave it harshly acidic and thin; over-blended raw cilantro turns it bitter and slick; overcooked, it goes dull and flat and loses the whole reason it exists.
Beyond the raw-versus-cooked split, it ranges from a thin table sauce to a thick, creamy verde enriched with avocado, and the chile choice tunes the heat from mild jalapeño to sharp serrano. The deeper structural contrast between this tomatillo green and the dried-chile red runs through all of Mexican cooking, and that comparison deserves its own article rather than being crowded in here.