Kuku Sabzi is packed with herbs and lightly spiced, this Persian side dish is usually made during New Year celebrations.
Heat 1 tablespoon oil in a 10-inch oven-safe nonstick skillet over medium-low heat. Swirl the oil to coat the pan. Add the leeks and cook, stirring occasionally, until very soft and translucent, about 10 minutes, then remove from the heat. Preheat the broiler.
Stir together the parsley, cilantro, dill, baking powder, turmeric, cardamom, cinnamon, cumin, eggs, ½ teaspoon salt and few grinds of pepper in a large bowl. Mix well until the eggs are incorporated (the mixture will be very dense and green). Stir in the leeks.
Wipe out the skillet and heat the remaining tablespoon oil over medium-low heat. Swirl to coat the bottom and sides of the skillet, then add the herb and egg mixture, pressing it into an even layer with a rubber spatula. Cover the skillet with a lid and cook until set on the bottom and about 2 inches in from the sides, 10 to 12 minutes. Remove the lid and transfer the skillet to the broiler. Broil the kuku, keeping an eye on it, until set completely in the center, 1 to 2 minutes. Using a rubber spatula, loosen the kuku from the bottom of the skillet and slide it onto a plate. Sprinkle with the walnuts and cranberries if using, then cut into 8 wedges and serve.