Layer lettuce, black beans, cheese and tomatoes in a glass serving bowl.
Place avocado in a medium bowl; mash well with a fork. Mash in lime juice. Sir in salsa, sour cream and salt mixing well. Spread mixture evenly over tomatoes spreading to edges of bowl to seal. Cover; refrigerate 1 to 2 hours.
Just before serving, sprinkle chips and cilantro over salad. Toss well and serve immediately.