PreparationFor dressing: Combine sumac with soaking liquid, 3 tablespoons lemon juice, 2 tablespoons pomegranate molasses, garlic, 2 teaspoons vinegar, and dried mint in a small bowl. Gradually add oil, whisking constantly, until well blended. Season with salt; add more lemon juice, pomegranate molasses, and vinegar to taste, if desired. For salad: Place pita pieces in a medium bowl; pour oil over and toss to coat. Season pita to taste with salt. Mix tomatoes and next 6 ingredients in a large bowl. Add 3/4 of dressing; toss to coat, adding more dressing by tablespoonfuls as needed. Season with salt. Add pita; toss once. Sprinkle sumac over, if desired.