Add chicken to a large bowl or ziplock bag. Combine marinade ingredients and pour over chicken. Stir well to coat and marinate for 1-4 hours.
Step 2
Meanwhile, make the tzatziki sauce by combining all ingredients. Taste it and add more seasoning (lemon juice, garlic, salt, pepper or cumin)if needed. Refrigerate.
Step 3
Heat grill to medium and oil the grates (or if cooking on the stove, add a little oil). Remove chicken from marinade, letting any excess sauce drip off.
Step 4
Grill chicken for a few minutes on each side, flipping once, until cooked through. Remove to a plate to rest before chopping into bite-size pieces.
Step 5
Toast or warm your pitas. Layer with chicken, lettuce, tomato, red onion, cucumber and sauce. Enjoy!