Gather all the ingredients.
Measure the cornstarch and water and whisk the mixture really well until there are no lumps. Tips: Make sure you DO NOT use warm or hot water as the slurry will start to thicken in an instant! It's good to prepare a slurry ahead of time so you won't end up with lumps.
Right before you finish cooking, adjust the heat to medium (or medium-low for a beginner cook) and get ready to add in the slurry to thicken the sauce/soup.
Mix the slurry one more time before adding to the sauce/soup as the cornstarch tends to settle at the bottom of the mixture.
Whisk the mixture as you evenly distribute into the sauce or soup.
The sauce or soup will thicken as you continue cooking over the stove. When it has almost reached the consistency you look for and develop a luster and become more translucent, remove from the heat. Tips: The sauce will continue to thicken with remaining heat, so don't overcook the food. You should not need to cook for more than 5 minutes after adding in the slurry.
Recipe by Namiko Chen of Just One Cookbook. All images and content on this site are copyright protected. Please do not use my images without my permission. If you’d like to share this recipe on your site, please re-write the recipe in your own words and link to this post as the original source. Thank you.