Dissolve the gravy granules in the boiling water. Set aside.
Add cider, absinthe and malt vinegar to a small pan. Simmer over medium heat and reduce the mixture down to 30ml, then add the prepared gravy and leave to simmer.
Coat the cheese in the flour, then add the cheese to the gravy mixture in the pan, ensuring it is not boiling. Stir gently until the the cheese is melted, then stop immediately.
Add the milk, butter and freshly ground black pepper, and stir gently. Simmer without boiling for one minute to keep warm, then serve.