Think of this dish as a warm Greek salad: tomatoes, bell peppers, olives and feta cheese all roasted together in cold-pressed olive oil, just waiting to get loaded onto fresh pita. We used green peppers here for a bright crunch that makes magic with the fragrant oil. Cooking the feta concentrates its salty taste, so sample it beforehand—you may want to mellow it out by soaking it in water first.