Instructions:

1. Marinate the chicken
   Step 1:

   In a mixing bowl, combine olive oil, lemon juice, minced garlic, oregano, cumin, paprika, cinnamon, allspice, cayenne pepper, salt, and black pepper. Add the chicken thighs to the marinade and coat them well. Cover the bowl and refrigerate for at least 2 hours or overnight for best results.
2. Cook the chicken
   Step 2:

   Preheat the grill or stovetop grill pan over medium-high heat. Cook the marinated chicken thighs for about 5-6 minutes per side or until they are cooked through and have a nice charred exterior. Use tongs to flip the chicken during cooking for even browning.
3. Slice and assemble the shawarma
   Step 3:

   Once the chicken is cooked, let it rest for a few minutes. Then, slice the chicken into thin strips. To assemble the shawarma, warm the pita bread or flatbreads. Place the sliced chicken on the bread and top with sliced tomatoes, cucumbers, and red onions. Drizzle with tzatziki sauce or hummus.
4. Serve and enjoy
   Step 4:

   Roll up the pita bread or flatbread with the chicken and toppings to form a delicious shawarma wrap. Serve immediately and enjoy the flavorful Greek Chicken Shawarma!