Instructions

1. Assess the quantity of liquid you are trying to thicken. If it is a soup, for example, your recipe may call for 3 qt. of broth. Cornstarch, arrowroot and potato starch require 1 tbsp. of thickener for each cup of liquid. Tapioca starch and flour require 2 tbsp.

2. Run cold water into a bowl or measuring cup, roughly 1 1/2 tbsp. of water for each 1 tbsp. of starch. Some starches dissolve more easily than others, so you may need to add a little more water. Whisk vigorously until the starch forms a thin, lump-free paste.

3. Whisk the cold starch paste into the hot liquid in small increments, always waiting until the first quantity is stirred in before adding more. Continue until all the starch has been added. To further minimize the risk of lumps, you can pour it through a fine-mesh strainer.

4. Cook the starch in the hot liquid until it has thickened adequately and there is no discernible taste of uncooked starch. Cornstarch works almost immediately, but only at a near-boil. Tapioca starch has a relatively low thickening point, making it a good choice for adding a small amount of last-minute thickening to a finished dish.

5. Serve hot sauces immediately. If you are making a pie filling or dessert sauce, cool it as directed and refrigerate until needed.