- Put tamarind residue in a nonmetallic bowl, add 1/2 cup boiling water, and let soak for 30 minutes. Mash the residue and extract as much tamarind essence as possible, squeezing it hard, into a bowl. Discard the fibrous residue.
- Put tamarind water in a nonmetallic pan along with cornstarch, mix well and bring to a boil. Cook for 2 minutes. Turn off heat and stir in ginger shreds.