In a large bowl, whisk together the olive oil, lemon juice, minced garlic, cumin, coriander, turmeric, paprika, cinnamon, cloves, black pepper, salt, and cayenne pepper (if using).
Add the chicken thighs to the marinade, ensuring they are fully coated. Cover the bowl and refrigerate for at least 2 hours, or preferably overnight, to allow the flavors to fully develop.
Preheat your oven to 400°F (200°C). Line a baking sheet with parchment paper.
Arrange the marinated chicken thighs on the prepared baking sheet. Transfer the baking sheet to the oven and bake for 20-25 minutes, or until the chicken is cooked through and slightly charred at the edges. If you want extra char, you can broil the chicken for an additional 2-3 minutes.
Let the chicken rest for a few minutes after cooking, then slice it into thin strips.
Serve the chicken slices in warm pita bread or flatbreads, topped with sliced tomatoes, cucumbers, red onions, fresh parsley or cilantro, and a generous drizzle of tzatziki sauce or garlic sauce.