Preheat the broiler. Roast the chiles under the broiler until charred all over. Transfer to a bowl, cover with plastic wrap and let steam for 5 minutes. Skin, stem and seed the chiles, then cut them into 1/3-inch dice. In a serving bowl, combine the chiles with the tomatoes, onion, olives, cilantro, olive oil and lime juice. Season with salt and pepper, toss to mix and serve.
The salsa can be refrigerated overnight. For a fresh taste, add the cilantro just before serving.