Roasted tomatillo salsa

Peel the papery husks off the tomatillos and rinse off the sticky substance under cold water.

Roast under a preheated broiler 5 minutes, flip, and 5 minutes on the other side, until blackened and blistered; the juice in the pan starts to caramelize.

Roast the serrano chilies in an ungreased skillet over medium heat, turning, about 10 minutes.

Roast unpeeled garlic cloves beside them 10 to 15 minutes, turning now and then, until soft and blackened in spots.

Cool the roasted ingredients and peel the garlic.

With the food processor running, drop in the garlic and serranos, then scrape in the tomatillos with their juice and blend to a puree; scrape into a bowl. A big batch can be held at this stage.

Rinse the chopped white onion to tame its bite and crisp it, shake off the water, and add it with chopped cilantro, a spoon of salt and a little sugar.

Stir, thinning with a little water if thick.