Put the saffron threads in a small bowl and grind with a mortal and pestle. Add a few tablespoons of hot water and set aside.
Add the butter to a cast iron skillet or a frying pan that can go into the oven. Bring the pan medium high heat and when the butter has melted add the cumin seeds and toast for about 2 minutes. Add the onion and saute for 5 minutes.
Pour the broth into a separate pot and bring it to a boil. When the onion is done, add the rice to the pan and stir to fully coat in the butter mixture. Cook for about 1 minute, then add the hot broth, saffron liquid, and salt.
Add the cast iron pan to the oven and cook for 30 minutes or until the rice is done. Let it cool for 10 minutes, then add the almonds, pomegranate arils and parsley. The saffron rice is ready to serve.