Prepare the onion, cabbage, bell pepper, and celery.
Heat olive oil in a pot and sauté the onion.
Add the cabbage, bell pepper, and celery, and stir-fry together.
Add diced tomatoes (or crushed tomatoes) and water, then bring to a boil.
Slice the carrots and add them in, then simmer over medium-low heat.
Season with salt and pepper, and simmer for an additional 20 minutes.