Season the chicken
Pat the Chicken dry, then season it all over with the Kosher Salt and freshly ground Pepper (Black). Let it sit while you prep the pot so the seasoning has a moment to sink in.
Brown the chicken
Heat 3 tbsp of the Ghee in a large heavy pot over medium-high heat. Add the Brined Chicken and brown it on all sides for 10 to 12 minutes, turning carefully until you get deep golden patches.
Simmer the broth
Lower the heat to medium, then add the Green Cardamom Pods, 3 beads of Mastic Resin, Dried Bay Leaves, Cinnamon Stick, Allspice Berries, Whole Cloves, and Black Peppercorns. Stir for 30 seconds until fragrant, then add the halved Yellow Onion, the halved head of Garlic, the Celery stalk cut into 2-inch pieces, the Sage sprig, and 1.9 liters of Water. Bring to a boil, reduce to a gentle simmer, cover partially, and cook for 35 minutes.
Strain and shred
Lift the chicken out to a board and strain the pot through a fine-mesh sieve into a bowl. Save the liquid for later, then pull the meat from the bones, shred it, and reserve about 1/2 cup as Shredded Chicken for garnish.
Cook the rice
Melt 2 tbsp ghee in the pot over medium heat. Stir in the Short-Grain Rice and cook for 1 minute until the grains look glossy. Measure 1.5 cups of the hot reserved Chicken Broth, add it to the pot with the Green Cardamom Pods, Bay Leaf, and the remaining 2 beads of mastic, then season lightly with salt and pepper. Bring to a boil, cover, reduce the heat to low, and simmer for 18 minutes; turn off the heat and let it stand, covered, for 10 minutes. Fluff with a fork before serving.
Blend the sauce
In a blender, combine 1.5 cups of the Walnuts, the crustless, lightly toasted White Sandwich Bread cut into 1-inch pieces, 2 cups of the reserved broth, the 3 minced garlic cloves, the Ground Coriander, Ground Cinnamon, Ground Nutmeg, and the Heavy Cream if you're using it. Blend until very smooth, and save the remaining 1/2 cup walnuts for garnish.
Toast the walnuts
Spread the reserved walnuts in a dry skillet over medium heat and toast for 3 to 4 minutes, shaking the pan often, until they smell nutty and are lightly browned. Tip them onto a plate right away so they don't keep cooking in the hot pan.
Thicken the sauce
Warm 1 tbsp ghee in a small saucepan over low heat, then stir in the walnut puree. Cook for 10 minutes, stirring constantly, until the sauce is thick and glossy; loosen it with a little more broth if it seems too stiff, and taste for salt and pepper.
Assemble and garnish
Lightly grease a serving platter with the Neutral Oil, then mound on the rice. Top with the remaining chicken, spoon the walnut sauce generously over everything, and finish with the toasted walnuts, Cilantro, and the reserved Shredded Chicken. Serve warm.
