Soak the porcini mushrooms in lukewarm water for 30 minutes; strain and reserve the liquid.
Heat olive oil in a frying pan, add mushrooms, parsley and saute’ gently for a few minutes; season to taste and set aside.
Heat stock in saucepan.
Saute’ onion in olive oil until slightly brown, add rice and let it toast until light brown, stirring constantly.
Add wine and liquid from the porcini mushrooms, stir until liquid evaporates.
Add mushrooms and a couple of ladles of hot stock, just until rice is covered.
Stir and simmer until nearly all the stock has been absorbed.
Continue this manner until all the stock has been used.
Once the rice is cooked (around 35 minutes), remove pan from heat, mix in Parmesan cheese and serve immediately.