Heat a large heavy-bottom pot over medium heat and add the olive oil.
Add the diced onions, garlic, onion powder, and Italian seasoning and cook until the onions are soft and the garlic is fragrant.
Add the salt and pepper, the chopped parsnip, chopped carrots, chopped bell pepper, and chopped celery, allowing the veggies to soften for several minutes, stirring regularly.
Deglaze the pan with the white wine, scraping any brown bits off the bottom of the pot.
Add the chopped zucchini, canned tomatoes, cabbage and vegetable stock.
Stir well, cover the pot, and cook for about 20 to 30 minutes, stirring regularly.
Add more salt and/or pepper to taste, if desired.
Serve in bowls with some freshly chopped parsley or basil (optional).