Peel the zucchini and cut into slices or pieces. Peel and chop the onion and garlic, sauté both in a little oil. Add zucchini and vegetable or meat stock, cook for 15-20 minutes. Add the sour cream and puree the soup. Cut the wiener sausages into thin slices and add to the soup, then let them steep for a few more minutes, season with salt and pepper if necessary.