1.Combine porcini mushrooms and the water in small heatproof bowl, cover, stand 15 minutes or until mushrooms are tender. Drain, reserve soaking liquid, chop mushrooms coarsely.
2.Cook pasta in large saucepan of boiling water until tender, drain.
3.Meanwhile, heat oil in large frying pan, cook pancetta until crisp. Add all mushrooms and garlic, cook, stirring, until mushrooms are browned lightly. Add wine, bring to the boil. Boil, uncovered, until liquid has almost evaporated. Add cream, juice and reserved soaking liquid, simmer, uncovered, until sauce reduces by half and thickens slightly. Stir in cheese and chives.
4.Combine pasta and sauce in large bowl. Serve sprinkled with extra cheese.
It is fine to use just 1 x 300ml carton of cream for this recipe. Porcini, also known as cèpes, are the richest-flavoured mushrooms. Though expensive, they are so strongly-flavoured only a small amount is required for any particular dish. They are available from specialty food stores and some supermarkets. Pancetta is an Italian salt-cured bacon. It is available from delicatessens and major supermarkets.