These are fresh sea coconuts that I bought from my neighbourhood wet market. This could be a seasonal fruit since I do not see them all year round at the market and never in the supermarket before. Sea coconut is believed to relieve heatiness, cough & phlegm (remember the cough syrup brand "非洲海底椰止咳露”? though I think most of the sea coconuts sold locally are imported from Thailand).
You can cook them as a sweet dessert with snow fungus (雪耳), candied dates (蜜枣) and Osmanthus flowers (桂花), or as a savory soup, as what I have done here. Pear and candied date are usually paired with apricot seeds (南北杏）to relieve cough. For this soup, the use of pear and candied date add sweetness to the soup while the sea coconut gives this soup a light coconut fragrance.