Roast the poblanos and jalapeno over an open flame (if you have a gas stove or a grill) or under a broiler until the skin is blackened and beginning to separate from the flesh. Once blackened on all sides, put in a plastic bag and set aside. This will allow the skins to easily be peeled off.
Toast sesame seeds in a large skillet over medium heat until golden, stirring occasionally. This will take 5 to 10 minutes. Add in pepitas and continue toasting until the pepitas start to pop, about 2 or minutes.
Add in the basil, onion, lettuce, zucchini, avocado, and chicken broth. Blend until smooth.
