Grate the half cucumber, toss with a small pinch of salt, and let it sit for 5 minutes in a strainer.
Squeeze the cucumber dry using a clean kitchen towel or paper towels.
Crush or mince your 4 cloves of garlic into a smooth paste.
Finely chop your fresh mint and fresh dill until you have about a tablespoon of each.
Combine the Greek yogurt, squeezed cucumber, garlic paste, chopped mint, chopped dill, lemon juice, salt, and black pepper in a mixing bowl.
Stir until uniform, then let it rest in the refrigerator for 20 to 30 minutes to let the fresh herbs and heavy garlic blend deeply into the yogurt.