To roast the tomatoes: Preheat the broiler. Lay the tomatoes on a baking sheet and place them about 4 inches below the broiler. Roast until blistered and blackened on one side, about 6 minutes. Turn the tomato to roast on the other side. Or place in a foil-lined heavy skillet over medium heat. Turn several times during cooking to blacken all around. Remove and cool. Peel the tomatoes, discarding the charred skins, collecting all the juices with the tomatoes.

To roast the jalapenos and garlic: Place the jalapenos and garlic on a broiler pan or in a heavy skillet. Roast, turning occasionally until both the jalapenos and garlic are blackened in spots and soft, about 5 to 10 minutes. Remove and cool. Pull the stems off the jalapenos and peel the papery skins from the garlic.

In a food processor fitted with the steel blade or blender, grind the jalapenos, garlic and 1/4 teaspoon of the salt until the mixture is a coarse paste, stopping to scrape down the sides of the bowl a couple of times. Add the tomatoes and pulse a few times until you have a coarse-textured puree.

Transfer the salsa to a serving bowl and stir in any reserved tomato juices.

In a strainer, rinse the onion under cold running water, shake off the excess and stir into the salsa along with the cilantro and, if desired, cider vinegar. Add water if necessary to give the salsa a thick but easily spoonable consistency. Taste and adjust seasonings with the remaining salt if necessary.

Cook's note: Substitute your favorite chile pepper for jalapenos.

>From "Rick Bayliss's Mexican Kitchen" by Rick Bayliss (Scribner, $35)

Tested by Susan Selasky for the Free Press Test Kitchen

6 calories (0% from fat), 0 grams fat (0 grams sat. Fat), 1 gram carbohydrate, trace of protein, 2 mg sodium, 0 mg cholesterol, 2 mg calcium, 0 grams fiber.