+1/2 tbsp. cornstarch dissolved in 3-4 tbsp. cool water

Cornstarch, also known as corn flour or maize starch, is a refined carbohydrate derived from the endosperm of corn (maize) kernels. It is produced by wet milling corn to separate the starchy component from other parts of the grain, then drying and grinding the starch into a fine, powdery substance. Cornstarch is virtually flavorless and odorless, appearing as a white powder with a silky texture. When suspended in cool liquid, it forms a slurry that acts as a thickening agent upon heating, a property known as gelatinization, where starch granules absorb water and swell, increasing the viscosity of the surrounding liquid.

Cornstarch slurry—cornstarch dissolved in cool liquid—is a fundamental thickening agent in cuisines worldwide, particularly in Asian cooking. It is used to thicken sauces, gravies, soups, and stir-fry liquids, where the mixture is added near the end of cooking to achieve the desired consistency without affecting flavor. The technique is favored because cornstarch produces glossy, translucent results, making it ideal for dishes requiring visual clarity, such as Asian stir-fries and sweet-and-sour preparations. It is also used in baking and dessert applications, and as a coating for fried foods to create crispness.