In a large saucepan, soften the cabbage and garlic in the butter, stirring frequently for about 10 minutes. Season with salt and pepper. Add the wine, broth and thyme. Bring to a boil. Cover, reduce the heat and simmer gently for about 30 minutes. Uncover and cook for about 15 minutes, stirring frequently until the liquid is almost completely evaporated. Add the vinegar and adjust the seasoning.