In a separate small bowl, whisk together the sour cream, vinegar, and 1/2 teaspoon salt until smooth and creamy. Taste and adjust the salt if needed.
Pour the creamy dressing over the cucumbers and toss gently until all the slices are evenly coated.
Cover the bowl and refrigerate for at least 15–20 minutes before serving to let the flavors meld. Give the salad a quick stir and taste again, adding a tiny pinch of salt if needed right before serving.
