In a large bowl combine all of the marinade ingredients and whisk together.
Place chicken in a gallon freezer bag and pour the marinade over it. Seal container and place in refrigerator to marinate for 4 hours.
When you are ready to cook the chicken remove from the bag and wipe off excess marinade. Then cook to an internal temperature of 165 degrees You can cook the chicken by grilling it, baking it at 400 degrees F for approximately 20 minutes, or cooking it in a skillet over medium high heat for 15-20 minutes.
Once the chicken is cooked through cut into thin slices.
Divide chicken, red onion, cucumber, tomato, olives, feta cheese, and tzatziki sauce between 4 bowls.
Serve with a squeeze of lemon and toss ingredients together before eating.