Shavings are cut off the block of meat for serving, and the remainder of the block of meat is kept heated on the rotating spit. Shawarma can be served on a plate (generally with accompaniments), or as a sandwich or wrap. Shawarma is usually eaten with tabbouleh, fattoush, taboon bread, tomato, and cucumber. Toppings include tahini, hummus, pickled turnips, and amba.
Shawarma is made by alternately stacking strips of fat and pieces of seasoned meat on a vertical spit. An onion, a tomato, or a halved lemon is sometimes placed at the top for decoration. The meat is roasted slowly on all sides as the spit rotates in front of, or over, a flame for hours. Some restaurants offer two or more meat selections; many have just one.
The meat is shaved off the stack with a large knife, an electric knife or a small circular saw, dropping to a circular tray below to be retrieved. Shawarma is eaten as fast food, made up into a sandwich wrap with pita or lavash together with vegetables and dressing. A variety of vegetables come with shawarma which includes: cucumber, onion, tomato, lettuce, eggplant, parsley, pickled turnips, pickled gherkins, pickles, rhubarb, cabbage, or French fries.
Dressings include tahini (or tahina), amba sauce (pickled mango with chili), hummus, or those flavored with vinegar and spices such as cardamom, cinnamon, and nutmeg. Chicken shawarma is served with garlic mayonnaise, toumaia (garlic sauce), pomegranate concentrate, or skhug (a hot chili sauce).
According to jamrahrestaurant.com