Place 3 tbsp lemon juice, oregano, 1/2 tsp salt, minced garlic and chicken breast in a large ziploc bag. Shake together and refrigerate for at least 1 hour or overnight.
Meanwhile, combine cucumber, yogurt, lemon juice, salt, dill and garlic together in a bowl. Mix well and set aside.
Remove from bag and alternate one piece of chicken and one piece of zucchini on a skewer. You should get about 4 skewers.
Heat a grill and once heated, grill the skewers for 8 minutes on each side or until chicken is cooked through.
Serve the skewers with the tzatziki sauce while hot
Recipe Notes
Substitute Bell peppers or tomatoes for the zucchini (also adds great color!)