Arabic Caesar Salad

Name: Arabic Caesar Salad
Ingredients: 1 clove garlic, minced; 1 cucumber; 1 cup watercress or any wild greens; 1 green bell pepper; 1 handful (about ¼ cup) coarsely chopped fresh cilantro or parsley; 1 handful (about ¼ cup) coarsely chopped fresh mint; 1 teaspoon salt, or to taste; 1 teaspoon za'atar, or to taste; 2 scallions, chopped (white and green parts); 2 tablespoons lemon juice; 2 tomatoes; 2 whole pitas (or 2 matzohs); 3 tablespoons extra virgin olive oil; ¼ teaspoon freshly ground pepper, or to taste; ½ medium onion