Too thin egg drop and hot and sour soup

I've made egg drop soup and hot and sour soup many times, always with corn starch. I've experimented with amounts of corn starch added to the broth, but it always turns out just as thin as it was before I added the starch. Am I doing something wrong, or does corn starch expire?

I don't want it gloppy like takeout, but a bit more body than plain store bought broth would be great.

Audrey Waller


SMSF January 30, 2018
Are you adding the cornstarch directly into the soup? If so, that could be the problem.
Try making a cornstarch slurry instead. Stir 2 or 3 teaspoons of cornstarch into a couple tablespoons of water until combined and not lumpy. Then add a small amount at a time to the hot soup. Be sure to let the soup come to a boil after adding the slurry or it won't thicken properly. Adding just some of the slurry at a time lets you control how thick the soup becomes. Hope that helps!
Audrey W. January 30, 2018
I have been using a slurry, even doubling the amount recipes call for.
SMSF January 31, 2018
Good that you're using a slurry. You need to bring the soup back to a boil after stirring it in or the soup won't thicken - maybe that's been the problem. Best of luck!
HalfPint January 30, 2018
Cornstarch as a thickener will tend to be thinner than other thickeners. Also if you overcook after adding cornstarch, the soup will get runny again.

If you are looking for something a bit thicker, try some others like potato or flour. These also have their pros and cons. Arrowroot also makes a light textured soup but cannot be reheat.

Here's a nice little guide:
Audrey W. January 30, 2018
I don't generally bring it back to a boil after I add the cornstarch, but I do usually add the vinegar before I add the starch-Spruce says to take it off the heat before you add the vinegar, maybe that's it.
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