Dice the onions and brown them in the oil. Add the pine nuts. When they become pink in color, add the rice and keep stirring for about 1/2 hour until the rice has become golden brown. A little before the rice turns this color, add the currants to give them time to expand. Then add 3 glasses of water (or 2 glasses of water and 1 glass of grated tomato). Reduce the heat to minimum, add the sugar, salt, pepper, mint. Leave covered 12 or 13 minutes until the liquid is absorbed. Extinguish the heat. Between the cover and saucepan, place 2 plies of absorbent paper to absorb the water vapor. Let stand 25 to 30 minutes, then place on a serving dish. Serve when completely cooled.