In a medium bowl, whisk together the yogurt, cucumber, garlic, lemon zest, lemon juice and dill. Season with salt and pepper. Chill.
BYOC: For some extra flavor, add some olive oil and some coarsely chopped fresh mint. Serve with crudities at your next party. Brush a pita with some olive oil and sprinkle za'atar on top. Bake in the oven until crispy and serve.