1. Combine the porcini and broth in a small saucepan and heat to
boiling. Cover and simmer over low heat for 10 minutes. Remove from
heat and let stand, covered for 20 minutes.
2. Drain the porcini through a sieve lined with a dampened paper
towel and set aside the broth separately. Rinse the mushrooms under
running tap water and rub with your fingers, cut off and discard
any gritty pieces. Drain well and pat dry. Finely chop and set aside.
(There should be about 1/2 and 3/4 cup of reconstituted dried porcini.)
3. Return the strained broth to the rinsed-out saucepan and heat
to boiling. Adjust the heat to maintain a steady simmer.
4. Heat 2 tablespoons of the butter and the olive oil in a heavy
saucepan over low heat until the butter is melted. Add the shallots
and sauté, stirring, until tender, about 3 minutes. Add the
rice and sauté over low heat, stirring for 2 minutes.
5. Add enough of the hot broth (about 1/2 cup) to just cover the
rice. Adjust the heat to maintain a steady simmer and cook the rice,
stirring constantly, until almost all the broth has been absorbed,
about 3 to 4 minutes.
6. Add another ladle of broth (about 1/2 cup). Cook stirring constantly,
until all the broth has been absorbed. Continue adding the broth,
about 1/2 cup at a time, and cooking and stirring. Add the next
ladleful when the broth is absorbed and the rice begins to pull
away from the sides of the pan as it is stirred.
7. About halfway through the cooking time add the reserved chopped
porcini. Cook until the rice is creamy and firm but not chalky in
the center when it is tasted. The total cooking time is 25 to 35
minutes or more.
8. Remove from the heat. Stir in the Parmigiano Reggiano and salt.
Sprinkle generously with black pepper. Serve at once with additional
cheese on the side.