Perhaps the most Norwegian of cheeses, the brunost – or brown cheese if you please – surprises most who taste it first time by being more reminiscent of toffee than cheese. But last week the cheese surprised firecrew and bystanders in the Arctic north of Norway when 27 tonnes of brunost caught fire on a truck inside a road tunnel, and kept burning out of control for five days solid. I chatted to The World on Public Radio International and BBC World Service about the unusual cheese melt: