Put tomatillos, jalapeños, onion & garlic into boiling water.
Simmer (don't boil) until tomatillos turn bright green, then olive green (took about 10 minutes, the tops of mine never turned olive green). Don't overcook or the the tomatillos will split open. Take vegies out w/slotted spoon into blender, add cilantro (I just took off the thickest stems) and purée.
Add cumin and more (raw) peppers or garlic if you want it spicier. Add cooking liquid to thin sauce if necessary.
Yields: