How to Make It
Soak the rice in lukewarm water for at least 1 hour and up to 6 hours; the longer the rice soaks, the fluffier it will be. After soaking, drain, rinse and add to a stockpot. Fill the stockpot with water and 1/2 teaspoon salt, bring to a boil over high heat, then reduce heat to medium once it starts boiling. Simmer until the rice softens and starts to freely float to the top of the water, about 8 minutes. Drain the rice and set aside.
In the stockpot (which should still be warm), add the 2 tablespoons coconut oil and line the bottom of the pot with potato slices. These will prevent the rice from drying and will also be delicious and crispy when the rice is done cooking. Alternatively, omit the potato, which will give the bottom rice a nice golden crunchy layer (called tahdig).
Scoop 1/3 of the rice into the pot, being careful not to shake the pot so that the rice doesn’t compact. Cover the rice with 1/3 of the chopped herbs. Spoon in another 1/3 of the rice, then another 1/3 of the herbs. Finally, add the remaining rice. Mix the melted butter (or ghee) with the crushed saffron, then pour over the rice in a circular pattern.
Wrap the stockpot lid in a kitchen towel, then cover. Cook on medium-high heat for 5 minutes, then reduce heat to low and simmer for 40 minutes. Uncover and carefully stir together with a spatula, then stir in the final 1/3 of the fresh herbs.
In a skillet, warm the ghee or coconut oil over medium-high heat for 1 minute. Combine the tapioca starch, salt, pepper and turmeric in a shallow pan. Dredge the fish fillets in the tapioca starch mixture one at a time, shaking off any excess starch. Add the fillets to the skillet (cook in batches if needed; don’t overcrowd the skillet). Cook for 3 minutes, carefully flip the fish, then continue to cook until the fish is done, about 3 more minutes, depending on the thickness of the fillets.
The fish is done when it just starts to flake (it will finish cooking when removed from the heat). If cooking the fish in batches, add more ghee/oil with each batch. Serve over the herbed rice.