Bring a large pot of water to a boil. Add corn and cook until crisp-tender, 2 to 3 minutes. Transfer to an ice-water bath to stop cooking. Drain and set aside.
In a medium skillet, cook pepperoni pieces over medium heat until browned, 3 to 4 minutes. Transfer to a paper towel-lined plate to drain and cool. Set aside.
In a small bowl, combine sour cream and lime juice. Season with salt and pepper.
In a large bowl, mix lettuce, corn, pepperoni, black beans, tomatoes and avocado. Distribute evenly among 4 plates. Offer sour cream dressing on the side. Serve with tortilla strips (see below) and corn bread, if desired.