One of the prevailing flavors is the olive oil. A favorite is extra virgin Bertolli, which you can buy in a big jug at Sam's. Sumac is available at Middle Eastern markets, or Penzey's in Beverly Hills (penzeys.com) Sumac's bright acidic flavor is key to the dressing. Parsley also adds a bright note. You don't have to use any mint leaves if you prefer it without. Toasted pita chips are widely available, but you could easily toast your own.