In a large mixing bowl, whisk together the Greek yogurt, olive oil, lemon juice, cumin, coriander, cardamom, smoked paprika, turmeric, cinnamon, cayenne, salt, and black pepper until well combined. Pat the chicken thighs dry and coat them evenly with the marinade. Cover and refrigerate for at least 3 hours, ideally overnight.

While the chicken marinates, prepare the garlic sauce by combining minced garlic and a pinch of salt in a food processor. Process until finely chopped, then drizzle in olive oil and lemon juice while blending until fluffy and creamy. Add a splash of ice water for consistency and blend again.

Heat a cast iron skillet or grill pan over high heat. Remove chicken from the marinade, letting excess drip off, and cook for 5-7 minutes on each side until charred and cooked through (internal temperature of 165°F). Let rest for 5 minutes.

Slice the chicken against the grain into thin strips. Serve warm inside pita or over a salad, drizzled with garlic sauce and desired toppings like cucumbers and tomatoes.