Put the porcini in a bowl with 250ml boiling water and leave to soak for 25 mins. Heat the oil in a pan and add the onion, carrot, garlic, rosemary and seasoning. Fry for 5 mins on a medium heat until softened. Drain the porcini, saving the liquid, and finely chop. Tip into the pan with the fresh mushrooms. Fry for another 5 mins, then add the stock, marsala or sherry, tomato purée, barley and strained porcini liquid.