6 fresh tomatillos, husks discarded and tomatillos rinsed
1 white onion, quartered
2 cloves garlic
2 jalapeno peppers, seeded if desired
1 1/2 cups water, or amount to cover
salt to taste
1/4 cup chopped fresh cilantro
1 tablespoon fresh lime juice, or to taste
3 ripe avocados, halved lengthwise and pitted
1. Place tomatillos, onion, garlic, and jalapeno peppers into a saucepan over medium heat, and pour in enough water to cover. Bring the mixture to a boil, reduce heat, and simmer until the tomatillos soften and change color from bright green to a yellow-green color, 5 to 8 minutes.
2. With a slotted spoon, transfer vegetables to a blender, filling the pitcher no more than halfway full. Hold down the lid of the blender with a folded kitchen towel, and carefully start the blender, using a few quick pulses to get the tomatillo mixture moving before leaving it on to puree. Puree until smooth, about 1 minute; mix in salt, cilantro, and lime juice. Blend again for a few seconds just to mix.
3. Scoop out the avocado flesh, and place into the blender; blend until well mixed. Adjust salt, cilantro, and lime juice before serving.