Season the chicken with the cumin, paprika, coriander, salt and pepper. In a large skillet, drizzle enough oil to just cover the bottom; heat over medium-high heat. Add the chicken and cook through, 7-8 minutes. Transfer to a plate; reserve the skillet.
In a food processor, pure the shallot, garlic, chipotle in adobo, vinegar and brown sugar. With the machine on, stream in EVOO. Pour into the reserved skillet and simmer the sauce for 1 minute.
In a large bowl, place the lettuce and onion. Add the avocado and dress with the lime juice. Top with the tomatoes, cilantro (or parsley) and chips. Pour in the warm dressing and toss. To serve, top the salad with the chicken.