Peel ginkgo nuts and remove the bitter center piths. Wash and drain peeled ginkgo nuts. Wash barley until water runs clear. Drain.
Combine ginkgo nuts, pearled barley, candied winter melon, and 7 cups (1.7 liters) water in a medium sized pot. Bring to a boil. Reduce heat to medium low and simmer for 1 hour.
In the meantime, break tofu sheets into small pieces. Soak in cold water to soften. Drain.
After boiling soup for 1 hour, add soften beancurd sheet to soup. Continue to boil for another 15 minutes. Turn off heat and remove.