CASU martzu. On first sight, a stinking, squirming vision of lactic hell, not so much cheese as maggot-infested nightmare. This Sardinian speciality (martzu means ‘rotten’) is made by slicing the top off a normal pecorino Sardo and allowing a special fly, Piophila casei, to lay her eggs within. In a couple of months, the larvae hatch into their own abundant food supply. And, as they semi-digest their edible nursery, the cheese begins to ferment, taking on a lusciously creamy texture, with a sharp, acidic tang.
I first tried it more than a decade ago, deep in the sun-bleached interior of the island, smeared over thin, crisp shards of local bread (also known as or ‘sheets of music’). It was
