Final answer:
To thicken a dish with cornstarch, first mix it with cold liquid to make a slurry, then add it to your simmering liquid and stir until the sauce thickens.
Step-by-step explanation:
Add cornstarch to thicken lots of dishes like desserts and stews. To avoid lumps, create a slurry. First, mix cornstarch with a cold liquid until smooth. Use liquid from your recipe or water. The ratio is typically 1 tablespoon of cornstarch to 2 tablespoons of liquid for every cup of liquid in your dish. Slowly stir this mixture into your hot, simmering liquid. Let it simmer until the sauce thickens and no longer tastes like raw starch, about 2 minutes. Cornstarch loses thickening power at higher temperatures, so add it towards the end of cooking. Use cornstarch for desserts and savory dishes, but it's not suitable to use as sweetener, protein supplement, or a source of lipids.