Roux
Roux () is flour and fat cooked together and used to thicken sauces. Roux is typically made from equal parts of flour and fat by weight. The flour is added to the melted fat or oil on the stove top, blended until smooth, and cooked to the desired level of brownness. Butter, vegetable oils, bacon drippings or lard are commonly used fats. Roux is used as a thickening agent for gravy, sauces, soups and stews. It provides the base for a dish, and other ingredients are added after the roux is complete.
Sausage gravy
Sausage gravy is a traditional Southern breakfast dish in the United States. After loose pork sausage is cooked in a pan and removed, a roux is formed by browning flour in the residual fat. Milk and seasonings, such as salt and pepper, are added to create a moderately thick gravy, to which the cooked sausage is added. Occasionally, ingredients such as cayenne pepper or a spicy sausage are used to make a spicier gravy.