How to Make It
Preheat the oven to 475°. Lightly coat a shallow roasting pan or rimmed baking sheet with vegetable oil spray. In a large bowl, combine the bell peppers, onion, zucchini, lemon juice, oil, oregano and a pinch each of salt and pepper. Transfer the vegetables to the pan and roast for 20 to 25 minutes, stirring, until crisp-tender.
In a nonreactive saucepan, coarsely mash half of the beans with the scallions, chipotles, garlic and cilantro. Add the remaining beans and season with the lime juice, salt and pepper. Cook over moderate heat, stirring, until warmed through, about 6 minutes.
Heat a large cast-iron skillet or griddle over moderate heat. Heat the tortillas, 1 at a time, until just softened, about 15 seconds per side. Transfer to plates and pile the beans and vegetables on top. Sprinkle with the cheese and roll up the tortillas. Top with the tomatoes and serve.