If you make this salsa just before serving it, the tomatillos will still be hot from the grill and give the salsa an appealing warmth. But you can also make it a day or so ahead, chill it, and serve it later—just let the salsa come to room temperature and hold off on adding the cilantro and scallion until it's time to eat.
Prepare a high charcoal or gas grill fire. Grill the tomatillos, covered, until charred on the bottom, about 5 minutes. Turn and cook until charred on the other side, 3 minutes more.
In a blender, purée the tomatillos, onion, lime juice, garlic, serranos, and a pinch of salt. Blend into a smooth sauce.
Transfer the salsa to a serving bowl. (If not serving immediately, cover and refrigerate for up to 1 week. Let the salsa come to room temperature before serving.) Add the cilantro and scallions, and season to taste with salt just before serving.
nutrition information (per serving):
per 1/4 cup;
sat fat g
Photo: Colin Clark