Cut the chicken breast into 1 - 1 1/2 inch pieces and set aside.
In a large bowl, mix olive oil with minced garlic, paprika, cumin, sumac, cayenne, salt and lemon juice.
Add the chicken pieces to the bowl and stir well so all pieces are coated with the marinade.
Cover with a plastic wrap, and place the bowl in the fridge. Marinate the chicken for at least one hour up to 24 hours.
Once ready to grill, take the bowl out of the fridge.
Heat the grill to medium heat.
Thread the chicken pieces and vegetables on skewers.
Once all the skewers are ready, start grilling the kabobs.
Grill one side for 5-8 minutes and then grill the other side. Make sure the kabobs are not undercooked.
Serve warm with your favorite side dish.