Wash the barley well. Add two cups of water, a pinch of salt, bring to a boil, lower the heat, place a tight lid on top and cook over a low heat for 1 hour. Stir. Blend half the cooked barley.
Heat one tablespoon of rapeseed oil over a medium heat and sauté the leek for one minute. Add the carrot and celeriac, pinch of salt and cook until tender.
In a large bowl place the whole barley, blended barley, cooked vegetables, chopped sage and thyme, grated cheddar. Mix well. Chop the Adrahan into small cubes and add to the mix. Season. Roll into small rissoles approx one tablespoon size.
Place the beaten egg into a flat dish and the bread crumbs into a 2nd flat dish. Dip the rissoles first into the egg and then coat in breadcrumbs. Set aside until ready to fry.
When ready to fry make the sauce
In a pan heat some oil and fry the mushrooms and thyme leaves. Add a pinch of salt. Continue to cook until all the liquid from the mushrooms has been reduced. Add the cream and wholegrain mustard and cook until the sauce thickens a little. Season.
Fry the rissoles in a little oil until crisp and golden brown.