Salsa de Tomatillos Como Las Asadas y Big Star
This recipe is definitely a "Medium" to "Mild" heat salsa. If you're interested in a "Hot" salsa, use 6-8 serranos. If you can't handle spicy at all, replace the serranos with another poblano. If you're really crazy, use 10+ serranos.
The salsa will have little black flecks of burned peel in it. Don't worry, it tastes fine! It's important to let the peppers steam themselves after roasting, to let the roasted flavor propagate to the flesh of the pepper. Putting the pepper directly in the boiling water and skipping that step will wash out this flavor somewhat.