A dark, unrefined, deeply caramel flavoured ‘black’ sugar is cultivated and processed on the Southern Japanese island of Okinawa. The almost constant sunshine, volcanic soils and nutrients provided by sea spray have created the ideal growing conditions for producing this mineral rich sweetener which has, quite naturally, found its way into a lot of both island and mainland Japanese cuisine. Pieces of the dense, almost raisiny tasting sugar are often consumed as a sweet along with green tea, or used as a flavouring in rafute pork stew, but our favourite way to use it is in these steamed cakes that we first encountered in a Tokyo depachika. Fresh from the steamer these light, airy cakes remind me of the geothermal, mountainous areas of Japan- their craggy, ruptured exterior, internal veins of rich gooey syrup and vents issuing jets of hot air. They are best eaten greedily, while still scalding hot, to really enjoy the texture and contrasting flavours of the delicate dough and the random nuggets of sugar.