1. Melt 2 tablespoons (30g) of butter in a large pot over medium heat, approximately 180°F (82°C).

2. Add 1 pound (450g) of ground beef and cook until browned, breaking it apart with a spoon as it cooks.

3. Next, add 1 medium chopped onion, 2 medium grated carrots, 2 medium diced potatoes, and 1 cup (115g) of shredded cabbage to the pot. Cook until the vegetables are slightly tender, about 5 minutes.

4. Add 1 can (14.5 oz/410g) of diced tomatoes, 1 cup (250ml) of tomato puree, 2 cups (475ml) of vegetable broth, and 1 cup (240ml) of water to the pot. Bring to a boil, then reduce the heat to low, approximately 150°F (65°C), and simmer, covered, for 10 minutes or until the vegetables are tender.

5. Season the soup with salt and pepper to taste. Serve hot, topped with a dollop of sour cream and chopped fresh parsley, if desired.