Cut the scapes into thin rounds. Sauté in butter for about 10 minutes at low heat. Place the potatoes and sautéed garlic in a sauce pan and add chicken broth. Cook covered for about 30 minutes. In small batches in your blender, pharmacy puree the soup until it is smooth. Return soup to the saucepan and add more broth if it is too thick. Add salt and pepper to taste, reheat. When hot, add white wine vinegar and serve.