Prep the cucumber: Grate the cucumber on the large holes of a box grater.
Toss it with a generous pinch of salt and let it sit in a fine-mesh strainer for 10 minutes.
Squeeze out the water: Wrap the grated cucumber in a clean kitchen towel or paper towels and squeeze firmly to remove as much moisture as possible. This keeps the sauce thick and creamy.
Combine the base: In a mixing bowl, add the Greek yogurt, minced garlic, 1 tablespoon olive oil, the zest of half a lemon, and 1 to 2 tablespoons lemon juice. Stir until smooth.
Add the cucumber and herbs: Fold in the drained cucumber and chopped dill.
Taste and adjust with more lemon, a splash of red wine vinegar for brightness, or a pinch of sugar if it tastes too sharp.
Season: Add salt and black pepper to taste. If the sauce feels too thick, loosen it with a teaspoon of olive oil or a small splash of water.
Rest: Cover and refrigerate for at least 20 to 30 minutes. Resting lets the flavors meld and the garlic mellow.
Serve: Drizzle with a little olive oil on top and a sprinkle of dill.
Pair with air-fried chicken, salmon, veggies, potatoes, pita, or falafel.