PREP. Clean tomatillos by removing the outer casing of papery leaves and rinse.
BOIL. Fill a medium saucepan with water and bring to a boil. Add tomatillos and jalapeños and boil covered for 15 minutes.
DRAIN. Drain water from pot and let tomatillos and jalapeños cool.
BLEND. In a high speed blender, combine tomatillos, jalapeños, garlic, cilantro, lime or lemon juice, water and salt to taste. Blend well, about 2 minutes. Add more water if needed.
TASTE. Add more salt, if needed.
SERVE.