Thickening a sauce without cooking it can be challenging since heat is typically required to activate thickeners and help them reach their full potential. However, there are a few techniques you can try to thicken a sauce without cooking it:
Cornstarch Slurry: Create a slurry by mixing cornstarch with a cold liquid, such as water or broth. Gradually add the slurry to the sauce while stirring continuously. The cornstarch will start to thicken the sauce, but keep in mind that it may not reach its full thickness potential without heat. The sauce will need to be heated at some point to allow the cornstarch to fully thicken.
Instant ClearJel: Instant ClearJel is a modified food starch that can be used to thicken sauces without cooking. It activates quickly when mixed with liquid. Follow the instructions on the packaging for the appropriate amount to use and mix it directly into the sauce until it thickens to your desired consistency.
Gelatin: Gelatin is a thickening agent that can be dissolved in cold liquid before being added to a sauce. Sprinkle gelatin powder over cold water or broth and let it sit for a few minutes until it forms a gel-like consistency. Then, add it to the sauce and stir well. Keep in mind that gelatin may not provide as much thickness as other methods and may require refrigeration to fully set.
It's important to note that while these methods may provide some thickening, the sauce may not reach its optimal flavor or texture without proper cooking. Heat helps ingredients meld together and can enhance the flavors and texture of a sauce. Therefore, for the best results, it is recommended to cook the sauce to allow the thickening agents to activate fully and to achieve the desired taste and consistency.