Preheat your broiler. Toss the tomatillo, onion and jalapeno in olive oil in a square glass baking dish. Roast for 15-20 minutes until everything starts to get charred.
Remove the vegetables from the oven, set aside and let cool for about 10 minutes.
Once they have cooled, toss the tomatillos, onion and jalapeno into a food processor or blender.
Puree until smooth, then place in refrigerator to cool.
When almost ready to serve, prepare your avocados and cilantro. Chop avocado into large chunks and roughly chop the cilantro. Toss together and add the juice of one lime.
Serve with chips and watch it disappear!