Heat a drizzle of oil in a large, ovenproof pan over medium-high heat. Add scallion whites and poblano. Cook until soft, about 4 minutes. Add tomatoes, beans, ¼ tsp chipotle powder (add more for additional heat), lime zest, reserved lime juice, and tortilla chips, stirring to combine and coat chips. Cook, stirring, until chips soften, about 2 minutes.