Preheat oven to 425°F (220°C) and lightly grease a large rimmed sheet pan.
In a large mixing bowl, whisk together the olive oil, lemon juice, minced garlic, cumin, coriander, turmeric, paprika, cinnamon, salt, and pepper until emulsified.
Add the chicken strips, sliced red onion, and bell peppers to the bowl, tossing thoroughly to ensure all surfaces are coated in the marinade.
Spread the chicken and vegetable mixture across the prepared sheet pan in a single, even layer to ensure proper roasting.
Place the pan in the center of the oven and roast for 20 to 25 minutes, or until the chicken reaches an internal temperature of 165°F (74°C) and the vegetables exhibit charred edges.
Remove from the oven and allow to rest for 5 minutes before serving with pita bread or tahini sauce.