Aunty Terese's Fattoush
1 small (4 inch) small pita bread round, spli… 1 small onion, diced 1 teaspoon sumac powder 2 tablespoons olive oil 2 tomatoes, diced 3 small cucumbers, halved lengthwise and slic… 5 leaves romaine lettuce, coarsely chopped 8 mint leaves, coarsely chopped ¼ cup coarsely chopped parsley, or to taste ½ teaspoon salt, or to taste ⅛ teaspoon ground black pepper, or to taste