Cut the dried mushrooms into smaller pieces. Soak them in warm water in a bowl. Chop the onion and garlic finely.
Heat up the chicken stock in a pot. It has to be hot by the time you mix it with the rice.
In a large saucepan, heat up the olive oil and half of the butter, then add the onions. Saute them on medium heat for about 3 minutes until they soften, then add garlic and saute for another 30 seconds.
Add the risotto rice. Stir occasionally for about 2 minutes, until the edges of the grains become transparent.
Pour in the wine, stir and let the liquid evaporate for another half minute.
Add one ladle of the hot stock at the time. Stir the rice, then let it absorb the stock. Repeat until the rice is cooked al dente. This takes 14 to 20 minutes, depending on the type of rice. Check the packaging for cooking time.
Add the mushrooms with the soaking liquid 1-2 minutes before the rice is cooked. Add salt and pepper to taste.
Take it off the heat, stir in the grated Parmesan cheese and the remaining butter. Cover and let it sit for 2-3 minutes. Stir it once more and serve hot.