Slice the chicken into thin strips.
Season with shawarma mentioned spices, buttermilk, olive oil, and lemon juice.
Marinate overnight for the best flavor, or at least 2 hours if you are short on time.
Place the chicken in the air fryer basket and cook at 180°C (350°F) for 12–15 minutes, until golden and juicy.
Slice the onions thinly and sprinkle them with salt.
Let them rest for about 30 minutes, allowing the water to release.
Transfer the onions to a colander and squeeze out the excess water.
Season with sumac for a tangy flavor.
Slice the lettuce into thin shreds and set aside.
Make the dressing : In a bowl, whisk together tahini, lemon juice, and yogurt until the mixture thickens.
Add water gradually, a little at a time, until you reach a smooth, mayonnaise-like consistency.
Season with salt and add one clove of mashed garlic for extra flavor.
In a large bowl, combine the cooked chicken with the seasoned onions and lettuce.
Toss everything together and drizzle with the tahini dressing.
Alternatively, arrange the ingredients in layers on a serving dish and serve the dressing on the side.