1. Preheat the oven to 190°C.
2. Cook the macaroni according to the packet instructions.
3. At the same time, melt the butter in a medium pan over moderate heat. Once foaming, add the flour and stir until it forms a paste. Cook for 5 minutes before slowly whisking in the milk. Continue to whisk to ensure the sauce (which will thicken to a smooth Béchamel sauce) is free of lumps. Reduce the heat and add the cheese, allowing it to melt into the sauce. Season with salt and freshly ground black pepper and stir through the vinegar.
4. Add the Fable to the cheesy sauce and use a wooden spoon to break the Fable down into smaller pieces. Finely chop the parsley (approx. 1 tablespoon) and add to the sauce, along with the cooked, drained macaroni.
5. Transfer the whole lot into a deep, suitable-sized ovenproof dish and bake in the preheated oven for 20-25 minutes until the surface browns. Remove from the oven and dust the surface with porcini powder before serving.
   

Note: Porcini powder can be made by blitzing dried porcini mushrooms in a spice grinder to a crumb. Pass the mixture through a fine mesh sieve, reserving the fine powder which stores well in a sealed container in your pantry.