Herb gravy is a type of sauce made from a combination of herbs, spices, and liquid such as broth, stock or milk, and is used to enhance the flavor of meat dishes, such as roasts, steaks, and chops. The herbs used in the gravy can vary, but common choices include rosemary, thyme, sage, and bay leaves. Other spices such as black pepper, garlic, and onion powder may also be added for extra flavor.