-ORgrated PRESSURE COOKER: Heat the oil in the cooker. Add the shallots and celery and cook, stirring frequently, until softened slightly, about 1 minute. Stir in the rice, chestnuts, currants, aniseed, salt, and water. Lock the lid in place and over high heat bring to high pressure. Lower the heat just enough to maintain high pressure and cook for 25 minutes. Allow the pressure to come down naturally or use a quick release method. Remove the lid, tilting it away from you to allow any excess steam to escape. If the rice or chestnuts are not quite cooked, return to high pressure for a few minutes. Drain (reserving the liquid for stock) and return to the pot. Cover and let steam over low heat for a few minutes to dry out. Fluff up as you stir in the orange peel. Break up chestnuts into 2 to 3 pieces with a fork, if desired. STANDARD STOVETOP: Soak the chestnuts overnight. Drain and reserve the water. In a heavy 2 litre saucepan, heat the oil. Add the shallots and celery and saute for 1 minute. Add the chestnut soaking liqiud plus enough water to equal 3 cups and bring to a boil. Stir in the rice, reserved chestnuts, currants, aniseed, and salt. Return to the boil, cover, reduce heat, and simmer until most of the grains have butterflied and almost all the liquid has been absorbed, about 50 minutes. Let stand, covered, off heat for 10 minutes. If there is still liquid left in the bottom of the pot, lift out the rice with a slotted spoon.