Wash the cucumber thoroughly, peel it, and finely chop it.
Add Greek yogurt and the chopped cucumber to a bowl.
Finely mince the garlic and add it to the bowl.
Pour in olive oil, lemon juice, and salt, then mix well.
Add chopped dill or mint leaves and mix once more.
Let it rest in the refrigerator for at least 30 minutes, then serve in a bowl.