Cozy Cabbage and Farro Soup

cabbage, savoy or green

Olive oil

medium onion, thinly sliced

Kosher salt and freshly ground black pepper

garlic cloves, smashed and peeled

sprig of rosemary or thyme (optional because I’ve forgotten it each time, and not regretted it)

red wine or white wine vinegar

uncooked farro

About 4 cups homemade or storebought chicken or vegetable broth

fresh lemon juice

Shaved parmesan, to finish