Start by combining the lemon juice, olive oil, minced garlic, ground cumin, paprika, turmeric, ground cinnamon, salt, and pepper in a bowl. Mix well until all the ingredients are fully incorporated.

Next, place the boneless chicken thighs (or breasts) in a shallow dish or a resealable plastic bag. Pour the marinade over the chicken, ensuring that each piece is well coated. Cover the dish or seal the bag, then refrigerate for at least one hour to allow the flavors to meld together.

For maximum flavor, you can marinate the chicken overnight. This will result in a more tender and flavorful chicken shawarma.

When you're ready to cook, preheat your oven to 425°F (220°C). Remove the chicken from the marinade and discard any excess marinade.

Place the chicken on a baking sheet lined with parchment paper or aluminum foil. Make sure to leave some space between the pieces of chicken to allow for even cooking.

Bake the chicken in the preheated oven for 15-20 minutes, or until the chicken is golden brown and cooked through. You can also broil the chicken for a few minutes at the end to achieve a slightly charred appearance, similar to grilling.

Once cooked, remove the chicken from the oven and let it rest for a couple of minutes. This will help the juices redistribute, resulting in a more tender and succulent chicken.

Now you're ready to enjoy your homemade chicken shawarma. Whether you choose to serve it in a warm pita bread, on top of a salad, or with a side of rice, the flavors of the homemade shawarma seasoning will surely impress your family and friends.