Rinse basmati rice until water runs clear. Cover again in water and let soak for 1 hour.
Brew saffron: add the saffron into a mortar and pestle with a pinch of salt. Grind into a fine powder and add ice. Let melt.
To a non-stick pot, add water and enough salt so that the water is as salty as the sea. Bring to a boil and add rice. Parboil until 70% of the way cooked–about 5 minutes. If unsure, give the rice a taste–it should be al dente with the center still slightly white and opaque. Pour the rice into a strainer and rinse with cold water to stop it from cooking.
In a nonstick pot, add the saffron water, oil, and turmeric. Mix well, then add rice back into the pot. The rice should be piled into a pyramid shape. Make a few holes halfway down to let steam escape. Cover the top with a towel and the lid. Place pot over medium-high heat for 15 minutes, then turn to low and let cook until the bottom is crispy and develops a deep golden brown color, about 50-60 minutes. You can check the doneness of the tahdig by lifting the edge with a rubber spatula.
To serve, place a plate over the top of the pot. Using gloves or a towel to prevent yourself from burning, hold both the plate and pot together, and flip in one swift motion. Serve.
