Wash the rice well in a number of changes of water until the water is almost clear when you rinse (around 4-5 changes of water). Finely chop the herbs and set aside.
Boil a pot of water, at least 3 cups, and add the salt and the rice. Cover and bring to a boil, reduce heat so that the pot doesn’t boil over and cook for around 5min.
Test the rice - it should be a little soft on the outside but still firm inside (‘al dente’). Drain in a colander, run under cold water (but on gentle pressure so it doesn't break up the rice). Mix the herbs through the rice.
Return the pot to the heat and warm the oil over a medium heat. Place a layer of the rice over the bottom and flatten down slightly, then add the rest in a slight pyramid over the top. Make three to five holes in the rice to allow steam to escape such as with the handle of a wooden spoon. Dot the butter on top, put a cloth over the lid of the pan to catch the steam then cover.
Start the heat on medium-high for around 5 - 10 minutes then reduce the heat to very low and cook for around 30 - 40 minutes in total.
Meanwhile, mix together the flour, salt, pepper, turmeric on a plate (if you like, you can also add a little dill). Dredge the fish fillets in the seasoned flour on both sides and shake off any excess.
Warm the oil in a large skillet and cook the fish for around 5 minutes on each side, depending on thickness of fillets, until cooked through.
To serve the rice, try to cover the pan with a plate and invert it so you get the crust on top, or else make sure you get the crust (tahdig) from the pan to enjoy alongside everything else.