In a skillet with oil, fry onion, garlic, chiles, tomatillos, and zucchini over medium heat until skin browns. Stir constantly for even browning.
Let cool and reserve oil. Place the cooled, cooked ingredients with oil in a blender.
Add cilantro and salt, and blend until smooth to a semi-thick consistency.
Serve salsa paired with your favorite tacos or serve as an appetizer with tortilla chips.
