For this recipe, I use 1 1/2 cups water to cook 1 1/2 cups basmati rice. That's a 1:1 ratio of water to rice. When you cook basmati rice in a pressure cooker, the 1:1 ratio makes fluffy basmati rice that cooks into individual grains that are tender but not overly soft. If you prefer softer rice, then use 1 3/4 cups water for this recipe. The rice won't be quite as fluffy and will clump together a little bit, but it's still tastes really good and has a softer texture. On the stovetop, more water is generally used to cook rice because the water evaporates while the rice cooks. In a pressure cooker, the water won't evaporate so you can use a 1:1 ratio.