Preheat oven to 400℉.
In a large frying pan heat 2 tablespoons oil over high heat. Add onions and saute 2 minutes until fragrant. Add Hawaij, salt and pepper and veggies or veggie meat of choice. Saute until browned and cooked and adjust seasoning to taste. Mix in ⅔ of the barberries reserving some for garnish. Set aside.
In a large pot, bring 5 cups water to a boil. Add 1 teaspoon salt and rice. Bring back up to a boil then cook for 5 minutes. Drain and set aside.
Combine the remaining 1 tablespoon water and saffron in a large bowl. Let stand for 5 minutes. Whisk in eggs, yogurt and 3/4 teaspoon each salt and pepper. Add parboiled rice and mix well.
Grease pan, (round cake pan or rectangular casserole) layer half of the rice and yogurt mixture. Top with chicken mixture over the rice, leaving a 1-inch border around the edge. Top with the remaining rice mixture, smoothing the top with a spatula. Pour butter over the top cover tightly with foil. Transfer the pan to the oven. Bake for 1¼ hours.
Let cool in the pan for 15 minutes. Remove the foil and run a knife around the edge to loosen the pie. Place a flat serving platter on top of the pan and carefully invert to release the pie from the pan.Scatter remaining barberries and chopped pistachios for garnish before serving.
Serve with tahini or herbed yogurt sauce and Israeli salad.