Rinse the rice several times in cold water until the water runs clear. Drain. Bring 3 quarts water to a boil in a large pot with 2 tablespoons kosher salt. Add the rinsed rice and boil, stirring occasionally, for 5 minutes, then drain well in a colander.

Heat 1 tablespoon butter in a small skillet over medium heat. Add the onion, season lightly with salt and cook until softened.

Add in 1 tablespoon saffron water and stir in the cinnamon, cardamom, allspice, black pepper and cumin. Cook for 1 minute more. Stir in the apricots, raisins or currants and barberries or cherries or cranberries.

Melt 4 tablespoons butter in a heavy-bottomed enamel or nonstick Dutch oven over medium heat. Spread half the par-cooked rice over the bottom of the pot. Spoon over the onion-fruit mixture, then the remaining rice. Leave the pot on the flame, uncovered, for 5 to 8 minutes to gently brown the rice. (Do not stir or move the rice)

Drizzle the remaining saffron water over the rice and put on the lid. Adjust the heat to very low and leave undisturbed for 30 minutes. Turn off the heat and let rest at least 10 minutes.

Heat the remaining 1 tablespoon butter in a small skillet over medium-low heat and gently toast the almonds and pistachios for a minute or so, taking care not to get them too brown. Set aside for garnish.

To serve, spoon the rice into a wide bowl or platter. With a spatula, carefully lift the bottom crust, placing the crisp side up.

Sprinkle with the toasted nuts and pomegranate arils.