Overnight, coat both sides of a roast with Sumac & fresh minced Garlic. Refrigerate.
Place roast in slow cooker w/ thinly sliced onions.
(IF the roast is very lean add a little olive oil &/or broth)
Cook on low all day
Pull beef apart & let simmer in juices while preparing the following
Serve for self assembly wraps w/ Hummus &/or Trader Joe's Tzatziki dip