Grass jelly is made by boiling the aged and slightly fermented stalks and leaves of ''Mesona chinensis'' with potassium carbonate for several hours with a little starch and then cooling the liquid to a jelly-like consistency. This jelly can be cut into cubes or other forms, and then mixed with syrup to produce a drink or dessert thought to have cooling properties, which makes it typically consumed during hot weather. The jelly itself has a slight bitter taste, a light iodine lavender flavor, and is a translucent black. It can also be mixed with soy milk to produce a milky white liquid with black strands in it.
In China, grass jelly was traditionally served with sugar syrup. Now it is often served mixed with other ingredients, such as mango, sago, watermelon, cantaloupe, and other fresh or canned fruit, and evaporated milk.
In Indonesia, black jelly is manufactured as an instant powder, like other instant jellies or agar. This form is easier to use. It is made from the leaves of ''Mesona palustris''.
Two other plants used in Indonesia are ''Melastoma polyanthum'', known as ''Cincau perdu'',
and ''Cyclea barbata'', known as ''Cincau Hijau''.
Malaysia and Singapore
Plain grass jelly is mixed in various kinds of desserts, such as ice kacang and ''cendol''. It is also mixed with soy milk to produce a milky white liquid with black strands in it, a drink known as Michael Jackson in South-East Asia.
In , grass jelly is ''th?ch'' . Grass jelly is chopped in small cubes and served as a additional ingredient in sweet desserts made from various kinds of beans . There are two common kinds of grass jelly in Vietnam which are - called ''s??ng sáo'' in Vietnamese and Tiliacora triandra called ''s??ng s?m'' in Vietnamese . Grass jelly drinks are also very popular amongst Vietnamese women; they are believed to enhance fertility, this is caused by the high levels of estrogen contained in the grass's root.
In Thailand grass jelly is known as, ??????? or chau guay, and is commonly served relatively plain with the addition of ice and natural brown sugar, in addition to the other preparations that are listed above, with the inclusion of fruits such as Jackfruit, the fruit of the and other Thai desserts.