While the cooked glutinous rice is still hot, pound it in a mortar to make a smooth paste, or blend it in your blender. Another method is to roll the cooked rice with a wet rolling pin. Keep folding the mass of rice over on to itself and rolling again, as if you were making puff pastry, until the grains are well mashed into each other. Keep the rolling pin wet so the rice doesn’t stick to it.
You can also make mochi by steaming the rice on a high heat for 10 minutes, then transferring it to a bowl and pouring over it an equal quantity of boiling water. Cover the bowl and let it stand for about 50 minutes, by which time the rice will have absorbed the water. Then put the rice back in the steamer and steam it again for 30–40 minutes.
This rice paste can be shaped as desired. It can be rolled into balls, to be used in soup, or cubes which can be kebabbed. In Japan, where mochi is an important part of the traditional diet, it is cut into small geometric shapes, sweetened and coloured for use in the tea ceremony.
For storage, roll the paste into cylinders or form it into rectangular blocks and wrap in greaseproof paper and an outer layer of foil. These can be refrigerated for up to 48 hours or frozen for up to 2 months. When you want to use them, let them thaw through completely, then reheat in boiling water for 5 minutes or steam for 5–10 minutes.