Potato and Cabbage Soup

Name: Potato and Cabbage Soup
Ingredients: 8 ounces bacon, cut into 1 inch slices (optional); 1 cup onion, diced; 1 cup carrot, diced (optional); 1 cup celery, diced (optional); 2 large leeks, rinsed and thinly sliced; 2 green onions, sliced and divided into lights and greens; 1/2 teaspoon caraway seeds; 6 cups chicken broth (link) or vegetable broth (link); 2 cups cabbage, chopped; 2 pounds potatoes, cut into bite sized pieces; 1/2 cup sour cream; 1 tablespoon white vinegar (optional); 1 tablespoon parsley, chopped (optional); salt and pepper to taste