Make Cabbage Soup in under 40 minutes: a cozy, tomato-scented bowl with cabbage and carrot that warms any evening.
Warm a large heavy pot over medium heat and add the olive oil, then cook the diced onion until it becomes translucent and tender, about 3–4 minutes. You want the onion to soften and release a sweet aroma without browning — a gentle, glossy translucence that will anchor the soup's savory base.
While the onion is cooking, cut the green cabbage into roughly ½" pieces. Add the chopped cabbage to the pot and continue to cook over medium heat until the cabbage begins to wilt and soften, about 8 minutes; you should see the cabbage turn a paler, slightly translucent green at the edges while still holding some structure. Prepare the remaining ingredients (open the can of diced tomatoes, shred the carrot, measure the tomato paste and seasonings) as the cabbage softens.

Stir the diced tomatoes with their juices, beef (or chicken) broth, shredded carrot, tomato paste, Italian seasoning, parsley, and the bay leaf into the pot with the softened cabbage and onions. Bring everything to a gentle boil, then reduce slightly and simmer uncovered for about 15 minutes, until the cabbage is tender and the broth has taken on a warm reddish-orange hue and a slightly thickened, glossy texture from the tomato paste.
Remove and discard the bay leaf, taste and season with salt and freshly ground black pepper, and ladle the soup into bowls to serve. The finished soup should read as a hearty, chunky broth with tender cabbage ribbons, plump diced tomatoes, thin carrot strands, and scattered flecks of parsley, warm and comforting on the spoon.
