Step 1

If using yogurt and milk, start at least 3 hours and up to a day in advance byplacing both in a bowl. Whisk well and leave in a cool place or in the fridgeuntil bubbles form on the surface. What you get is a kind of homemade buttermilk, but less sour.

Step 2

Tear the bread into bite-size pieces and place in a large mixing bowl. Addyour fermented yogurt mixture or commercial buttermilk, followed by the restof the ingredients, mix well, and leave for 10 minutes for all the flavors tocombine.

Step 3

Spoon the fattoush into serving bowls, drizzle with some olive oil, and garnish generously with sumac.