Place the shredded cucumber in a bowl and add 1/2 teaspoon of salt to it. Toss to combine.
Put this mixture on a cheesecloth and squeeze all the water out of the cucumber. Take as much moisture out as you can to avoid a runny sauce.
In another bowl, whisk together the garlic, apple cider vinegar, olive oil, and the remaining salt.
Add the shredded cucumber to this mixture along with the Greek yogurt, dill, and black pepper.
Mix it and cover the Tzatziki sauce and place it in the fridge for at least 30 minutes to allow the flavors to come together.
Greek Seasoning;
Mix all ingredients and set aside.
Chicken Souvlaki;
Place the chicken in a bowl and add lemon juice, olive oil, and 1 tablespoon of the seasoning to it. Mix until the chicken is covered in the marinade completely.
Cover the chicken and place it in the fridge for 1-2 hours.
Set your grill or griddle to medium-high heat and let it come to a temperature of 375°F-450°F.
Thread the marinated chicken cubes onto metal skewers and place them onto the grill or griddle.
Cook the chicken for 5-6 minutes per side with the lid closed. You're looking for a golden brown color on the outside and an internal temperature of 165°F.
Place the skewers on a platter and serve with warm pita bread. Serve the Tzatziki sauce in a bowl and garnish with two cucumbers on top.