Which technique is used to create a thickening by cooking flour with fat?

• A. Roux
• B. Slurry
• C. Saute
• D. Simmering

Answer: (A)

Roux is the technique of thickening a sauce by cooking flour with fat. By melting fat and whisking in flour, you cook the raw starch and create a smooth paste that can hydrate evenly when liquid is added. This gives sauces body and a glossy texture, and the amount of cooking time changes the color and flavor (white, blond, or brown roux) while preserving the thickening power. A slurry, on the other hand, thickens with starch dispersed in cold liquid and is added to hot liquid without being cooked in fat, so it isn’t about cooking flour with fat. Saute is simply cooking food quickly in fat for flavor and color, not a thickening method. Simmering describes the cooking stage in liquid, not the technique used to thicken with flour and fat.