1 (3/4-ounce) package dried porcini mushrooms
1 cup hot water
2 Tablespoons unsalted butter
1 Tablespoon olive oil
1 medium red onion, chopped
1 garlic clove, minced
10 to 12 button mushrooms, sliced
2 cups arborio rice
1/2 cup red wine
6 cups vegetable stock, heated
1/4 cup (1/2 stick) unsalted butter
2 ounces Parmigiano-Reggiano cheese, grated
Salt and pepper to taste
Soak the porcini mushrooms in the hot water in a bowl for 30 minutes. Drain, reserving the liquid. Rinse the mushrooms and slice.Heat 2 Tablespoons unsalted butter and olive oil in a large skillet. Saute the onion and garlic in the butter mixture for 2 minutes. Stir in the button mushrooms. Saute for 3 minutes. Add the rice and mix well.
Saute for 1 minute. Stir in the wine. Cook until the wine evaporates, stirring constantly. Add 1 cup of the hot stock. Cook until the stock is absorbed, stirring constantly. Add the porcini mushrooms and 1 cup of the remaining stock. Cook until the stock is absorbed, stirring constantly. Pour the reserved mushroom liquid through a fine strainer into the rice mixture and mix well.
Add the remaining stock 1 cup at a time, stirring constantly and cooking until the stock is absorbed after each addition. This will take approximately 20 minutes. Remove from the heat. Stir in 1/4 cup unsalted butter and cheese. Season with salt and pepper. Serve immediately.