Begin by preparing your vegetables, as this soup relies on fresh, properly chopped ingredients for the best texture and flavor. Chop 1 head of cabbage into bite-sized pieces, dice 1 large yellow onion, and cut 2 green bell peppers into chunks.
Slice 1 bunch of celery and peel and chop 5-6 large carrots into rounds or sticks. Heat 1 tablespoon of extra virgin olive oil in a large pot over medium heat, then add the onion, bell peppers, and celery. Sauté these aromatic vegetables for about 5 minutes until they begin to soften and release their flavors into the oil.
Add the chopped cabbage and carrots to the pot, stirring well to combine with the sautéed vegetables. Pour in 1 (46 fluid ounce) can of low-sodium V8 juice and 1 (14 ounce) can of Mexican-style tomatoes, including their liquid.
Stir in 1 (7 ounce) can of mushrooms with their liquid and sprinkle in 1-1 7/8 ounce vegetable soup mix to season the entire pot. Bring the mixture to a boil, then reduce the heat to low and allow the soup to simmer for 25-30 minutes, or until all the vegetables are tender and the flavors have melded together.
Taste the soup and adjust the seasonings as needed, adding more salt, pepper, or herbs to suit your preference. If you prefer a brothier consistency, add additional V8 juice or vegetable broth. Ladle the hot cabbage soup into bowls and serve immediately.
This recipe yields approximately 8-10 servings and can be stored in the refrigerator for several days or frozen for later enjoyment.