Preheat the oven to 375°. With a knife, trim the edges from the pita bread to form rounds. Cut each round into 8 wedges. Arrange the pita wedges on a baking sheet and drizzle with oil. In a bowl, combine the salt, pepper, thyme, parsley, shallot, sumac and sesame seeds. Sprinkle the mixture evenly over the pita chips. Bake until crisp, 10 to 12 minutes.