Vegetarian

Melt the butter in a large heavy pot over medium heat
Add the onion and sauté until translucent
Add the cabbage, carrot, and celery and sauté until they begin to soften, about 3 minutes
Add the bay leaf and vegetable stock, bring to a boil, then reduce heat and simmer, covered, until vegetables are crisp-tender, about 15 minutes
Add the potatoes, bring to a boil, then reduce heat and simmer, covered, until potatoes are tender, about 10 minutes
Add the tomatoes and simmer uncovered for 5 minutes, then season to taste
Remove and discard the bay leaf
Serve topped with sour cream and dill