In a small bowl, mix olive oil, lemon juice (or the rinsed and chopped peel from one preserved lemon). Add crushed garlic, salt, za'atar, ground sumac, and bezar. Whisk to incorporate the ingredients.
Drizzle marinade over chicken pieces and work into the flesh to infuse the marinade flavor. Place in a large bowl or a plastic ziplock bag and refrigerate for a minimum of 2 hours or overnight.
Preheat oven to 375°F. Arrange chicken thighs into a large cast-iron skillet (or other oven-safe pan or dish). Bake for 45 minutes or until the chicken reaches an internal temperature of 165°F. If the skin is not crispy and brown, broil for a few minutes longer.
Grilled Za'atar Chicken
Another option is to grill the marinated chicken instead of baking it. To do so, grill za'atar marinated chicken thighs over medium high heat until they reach an internal temperature of 165°F.
Notes
Zaatar chicken can also be prepared with a whole chicken, drumsticks, and chicken breasts. The baking time would need to be adjusted accordingly.