Borscht

Based on Helga's Russian Borscht recipe. I make mine without meat.

1 onion, peeled and finely chopped
3 1/2 quarts beef broth
1/4 cup red wine vinegar
2 tablespoons lemon juice
1/2 head cabbage, cored and shredded
1 1/2 pounds ripe tomatoes, diced
4 beets, peeled and diced
3 carrots peeled and diced

Fat-free sour cream for topping

Combine all, except sour cream in crockpot. Cook for 8 hours on low until vegetables are tender. Garnish individual servings with dollop of sour cream if desired.