Constanza Guimares is our invaluable housekeeper. When I asked her how the Portuguese would use mushrooms, she came up with the idea of combining them with what is probably the most used and best-loved ingredient in Portugal - bacalau, the salt cod from Norway. The recipe sounded so homely and comforting that I had to have a go, and here it is, using the very large brown cultivated Portobello mushroom.
