In a mixing bowl, whisk together the cumin, paprika, turmeric, cinnamon, minced garlic, lemon juice, Greek yogurt, olive oil, salt, and pepper until fragrant and well combined.
Trim any excess fat from the chicken thighs and cut them into large chunks for even cooking.
Add the chicken pieces to the bowl and toss thoroughly to coat each piece evenly with the spice marinade. Let sit for 10 minutes to absorb flavors.
Transfer the seasoned chicken into your slow cooker, spreading it out in an even layer. Cover with the lid.
Set the slow cooker to low and cook for 6 to 7 hours, or until the chicken is tender and falling apart.
Once cooked, use two forks to shred the chicken directly in the slow cooker, mixing it with the flavorful juices.
For a smoky, charred edge, transfer the shredded chicken onto a baking sheet and broil in the oven at 200°C (390°F) for 3-4 minutes until edges are crisp and darkened.
Remove from the oven and let rest for a few minutes. This helps the juices settle and keeps the chicken tender.
Serve the shawarma in warm pita pockets, over rice, or in salads, garnished with fresh herbs if desired.
Enjoy the fragrant, smoky, tender chicken shawarma with your favorite sides!