This recipe makes a pretty big batch, so you may want to cut it in half. Warning -- there are a lot of steps, but it's still an easy dish to make, and the end result is so much better than any "fresh" salsa sold in the supermarket, so it's well worth the effort.
I start with a bunch of ripe green tomatillos of varying sizes (about 20 or so). Since tomatillos grow in a thin, paper-like husk, it is important to inspect each, one by one, by carefully lifting the husk, to ensure each tomatillo has a bright green appearance and a smooth, shiny skin.
First, I remove the husks and wash the tomatillos in warm water to rid them of their slightly sticky residue. Then I put them in all in a pot, along with 1 jalapeno pepper, 1 Serrano pepper, a teaspoon of salt, and just enough water to barely cover the tomatillos and peppers. I bring the water to a boil, and as soon as the smaller tomatillos start to soften, I turn off the heat and let everything cool down. I intentionally cook them unevenly -- some more done, some less done -- so that my finished salsa will have a rustic texture.
Next, I roast two poblano peppers right on the burner over a low flame, turning frequently until they are charred on all sides. When those are ready, I plop them into a plastic or paper bag, close it up, and let them sweat. When they are cool enough to handle, I remove the skin and the seeds and dice them up and set them aside.
In the meantime, I dice 1 medium white onion, 2 scallions (including the green parts) and a large bunch of cilantro (including some of the stems, which are packed with flavor). I add to that mixture 1 very finely diced jalapeno pepper and set that aside. (Note you may choose to include or omit the seeds and membranes of the jalapeno, depending on how spicy you like your salsa.)
Then I put the cooked tomatillos in a food processor or blender, along with the cooked jalapeno and Serrano peppers. (I chop up the cooked peppers a bit first, and keep in all the seeds.) To that I add about a cup of the diced onion-pepper-cilantro mixture, 1/2 teaspoon of cumin, 1/2 teaspoon of salt, 1/4 teaspoon of black pepper, 1/4 teaspoon of sugar, and the juice of one lime. You made need to do this part in batches if you are working with a smaller food processor, like I am.
Next I blend everything altogether on pulse mode, adding small amounts of the reserved cooking liquid until the consistency is just right, and pour it all into a bowl. It should look like this.
I then add the remaining chopped onion-cilantro-jalapeno mixture to the salsa as well as the roasted and diced poblano peppers, stir it all together, and adjust the seasonings.
If the salsa verde is not hot enough for your taste, chop up and add more fresh jalapeno and Serrano peppers. If it's too hot, don't worry -- the heat will mellow as the salsa cools and the flavors marry. Cover and refrigerate for at least an hour.
Salsa verde is really a wonderful and versatile condiment that livens up many dishes and makes vegan eating all the more enjoyable, but of course nothing beats a bowl of it, all on its own, with some excellent tortilla chips.