Put 50g dried porcini mushrooms into a large bowl and pour over 1 litre boiling water. Soak for 20 mins, then drain into a bowl, discarding the last few tbsp of liquid left in the bowl.
Crumble 1 vegetable stock cube into the mushroom liquid, then squeeze the mushrooms gently to remove any liquid.
Heat 2 tbsp olive oil in a shallow saucepan or deep frying pan over a medium flame. Add 1 finely chopped onion and 2 finely chopped garlic cloves, then fry for about 5 mins until soft.
Stir in 250g chopped chestnut mushrooms and the dried mushrooms, season with salt and pepper and continue to cook for 8 mins until the fresh mushrooms have softened.
Tip 300g risotto rice into the pan and cook for 1 min. Pour over a 175ml glass of white wine and let it bubble to nothing so the alcohol evaporates.
Keep the pan over a medium heat and pour in a quarter of the mushroom stock. Simmer the rice, stirring often, until the rice has absorbed all the liquid.
Add about the same amount of stock again and continue to simmer and stir - it should start to become creamy, plump and tender. By the time the final quarter of stock is added, the rice should be almost cooked.
Continue stirring until the rice is cooked. If the rice is still undercooked, add a splash of water. Take the pan off the heat, add 25g butter and scatter over 25g grated parmesan or Grana Padano cheese and half a handful of chopped parsley leaves.
Cover and leave for a few mins so that the rice can take up any excess liquid as it cools a bit. Give the risotto a final stir, spoon into bowls and scatter with the remaining 25g grated cheese and the remaining chopped parsley leaves.
