For the colorful potato salad, boil the potatoes. Then rinse and peel. After cooling, cut into cubes.
Peel and dice the onions. Bring to a boil with a good 125 ml vinegar, water, clear soup, 1/2 tsp salt and pepper. Pour over potatoes and let cool. Fold in oil.
Chop tomatoes, cucumber and radish. Finely pluck basil. Mix all ingredients carefully with the potatoes.
Let stand for a short time. Season again with salt and freshly ground pepper.