Slice the cucumbers thinly and place them in a colander. Sprinkle a little salt over them and let them sit for about 5 minutes to release excess water.

In a large bowl, combine the sour cream, mayonnaise, vinegar, salt, and pepper. Whisk until smooth and creamy.

Rinse and drain the cucumbers, then add them to the bowl along with the diced tomatoes and chopped red onion.

Carefully toss everything together until the vegetables are well-coated in the creamy dressing.

Let the salad sit in the refrigerator for at least 30 minutes before serving, allowing the flavors to meld beautifully. Garnish with dill or parsley just before serving.