Heating the sauce might slightly change its flavor. But, if you want to thicken it up a little, mix together very well 1/4 cup of the cool or room temperature sauce with 2 teaspoons of cornstarch. Bring the remaining sauce to a simmer. Briskly whisk in the sauce/cornstarch mixture. Let it simmer for about 1 minute or so.
This is for 16 ounces of sauce. You will need to adjust the amount of cornstarch if thickening more or less sauce.
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