The rice may take approximately an hour to cook. Please remember that the variety, maturity and age of the rice, together with the quantum of heat decides the cooking time. So, the best thing to do is to lift out a few grains of rice now and then, and squeeze gently between your thumb and forefinger. As soon as the rice is soft and yielding, devoid of any hardness at the center, you can tell that it is cooked perfectly.