The herb contains substances that are useful for improving digestion and increasing circulation. In cooking, rosemary is used as a seasoning in a variety of dishes, such as soups, casseroles, salads, and stews. Use rosemary with chicken and other poultry, game, lamb, pork, steaks, and fish, especially oily fish. It also goes well with grains, mushrooms, onions, peas, potatoes, and spinach.