In a large mixing bowl, combine freshly minced garlic, cumin, paprika, turmeric, coriander, cinnamon, cayenne pepper, salt, and black pepper. Mix until evenly distributed. Add olive oil, plain yogurt, and lemon juice, stirring to create a smooth marinade.

Place the boneless skinless chicken thighs in the slow cooker. Pour the prepared marinade over the chicken, ensuring each piece is well-coated. Gently toss if needed.

Cover and cook on low for 6 to 8 hours or on high for 3 to 4 hours. The chicken is done when tender and easily shredded with a fork.

Carefully shred the chicken directly in the pot using two forks, mixing with the remaining juices to enhance moisture and flavor.

Serve in warm pita with the shredded chicken, adding fresh vegetables like cucumbers and tomatoes. Top with feta cheese or pickled onions if desired.