One of the most popular sweets soups in Hong Kong is tapioca soup 西米露. Thanks to the restaurant chain 許留山, mango tapioca soup has become one of the household desserts in Hong Kong. Tapioca soup is actually extremely easy to make at home, and at a fraction of the price you pay at a sweet soup vendor. Since it's a soupy mixture, the proportions of the ingredients are kind of ad lib. - there's no need for finicky precision like baking a cake.
Since good mangoes are impossible to come by in the States, I decided to make melon tapioca soup instead. I like to mix different kinds of melons for a more interesting flavour, but you can stick to only one kind if you wish. The same method of preparation goes for other fruits like mangoes and watermelon (very popular in Hong Kong), although I'm yet to encounter strawberry or banana tapioca soup... Anyone?