Wash and core the apple, then cut into small pieces with the peel. If you don`t want a peel on the apple, you can peel it. Wash the celery, peel off the protruding threads and cut into thin slices.
Pour the yogurt into a bowl. Add apple, celery and garlic to the yogurt and stir.
Season with vinegar, oil, salt and pepper and season to taste.
Tip: The salad tastes even better if it sits through for a few hours.