You cook it long enough for the grains to change color. The rice grains absorb the fat and kind of become translucent? You'll know it when you see it. You have to stir it pretty often, not constantly, but close.
You can also cook it long enough for the grains to start browning. The flavor gets nuttier, the best way I know to describe, the longer you cook it.
Yes, jasmine and basmati are usually 1 part rice to 1.5 liquid.
Our favorite and simplest pilaf is to first sautee in half and half butter and oil chopped onions and celery, then add some chopped mushrooms then add the rice (long grain), chicken stock for liquid, S and P, bring to a boil, turn off heat and let sit for 20 minutes at least while rest of meal cooks.