Prepare the bread by brushing the pita loaves with olive oil and heating them in the oven at 200C for 15 minutes till they are crisp. Break the crisped bread into shards. You can use any other flatbread.
Make the dressing by adding all ingredients to an airtight jar and giving it a brisk shake. Alternatively, add them to a bowl and briskly whisk them together till you have an emulsion.
In a large bowl, put all the chopped vegetables and leaves of the salad along with the bread shards. Pour over the dressing and give it a good mix.
Sprinkle some sumac over the top. Your fattoush salad is ready!
Notes
You can add some grilled chicken if you want to make this a meal.