For the dressing, blend all ingredients together in a blender or food processor until smooth (adding additional olive oil if needed). Add salt and pepper, to taste. Refrigerate until ready to serve.
Preheat oven to 350 degrees F.
Toss together the pita bread pieces, olive oil, and salt. Spread the pita pieces evenly on a large baking sheet. Bake until golden brown and crisp, 12-15 minutes. Allow the pita to cool completely before preparing the salad.
In a large salad bowl, combine the tomatoes, cucumber, parsley, and feta. Just before serving, add the pita chips and toss the salad in the olive oil, lemon juice, and salt. Serve immediately, with Yogurt-Feta Dressing drizzled over the top or served on the side.