The word "baccalà" or salted cod derives from Portuguese "bacalhao" which, in its turn comes from the Flemish word "bakkaliaum", and refers to cod preserved in salt, while the dried variety is known as stockfish. Credit must be given to the Dutch for the idea of salting cod as they introduced this technique in the sixteenth century directly on their fishing boats.
In a wide bottomed pan, brown the onion and the garlic in hot oil. Then add the moistened, salted cod and leave to cook adding a little milk and vegetable stock. Season with very little salt and pepper and sprinkle with a little flour. Mix vigorously so that the cod breaks up and becomes a homogenous, creamy mixture. Leave to cool well and then fill the cannelloni. Arrange in a buttered baking dish, pour over the soft béchamel and bake at 180 degrees for 20 minutes. In a pan with a little oil, brown the leek and potato, add a little stock and allow the mixture to become creamy. Reduce to a fine sauce using a hand blender and season with salt and pepper. Pour the potato sauce on the bottom of the plate and arrange the hot cannelloni on top, garnishing with slivers of truffle and a slice of fried pumpkin.