Preparing Authentic Homemade Chicken Shawarma is straightforward if you follow these detailed steps:

1. Prepare the Chicken: Begin by trimming any excess fat from the chicken thighs. Cut them into even pieces for uniform cooking.
2. Make the Marinade: In a large mixing bowl, combine minced garlic, cumin, coriander, paprika, turmeric, cinnamon, cayenne pepper, yogurt, olive oil, lemon juice, salt, and black pepper. Mix well.
3. Marinate the Chicken: Add the chicken pieces to the marinade, ensuring they are well-coated. Cover and refrigerate for at least 1 hour, preferably overnight for optimal flavor.
4. Preheat the Grill or Oven: If using an outdoor grill, preheat it to medium-high heat. If using an oven, preheat to 425°F (220°C).
5. Cook the Chicken: If grilling, place the marinated chicken directly on the grill. Cook for about 6-8 minutes on each side, or until the chicken is cooked through and has a nice char. If using an oven, place the chicken on a baking sheet and roast for 20-25 minutes, or until fully cooked.
6. Let the Chicken Rest: Remove the chicken from the heat and allow it to rest for about 10 minutes. This helps the juices redistribute.
7. Slice the Chicken: Once rested, slice or shred the chicken into thin strips.
8. Prepare the Pita and Veggies: While the chicken rests, prepare your pita bread and chop any fresh vegetables you plan to use.
9. Assemble the Shawarma: Place a generous amount of sliced chicken into a warm pita bread, top with fresh vegetables, and drizzle with tahini or garlic sauce.
10. Garnish and Serve: Sprinkle with fresh parsley for added flavor and presentation. Wrap the pita and enjoy your amazing homemade shawarma!