Toast and grind the walnuts in one of two ways. Either spread them out in a single layer in a large skillet, and toast them on medium high heat, stirring frequently until lightly toasted, OR spread them out in a single layer in a baking rimmed baking sheet, and toast at 350°F in the oven for 8 to 10 minutes. In either case, once toasted, remove from heat and allow to cool.
Season chicken with salt, pepper and turmeric. In a large pan or Dutch oven, heat 2 tablespoon of olive oil over medium-high heat. Place chicken pieces in pan, working in batches if necessary to not crowd the pan, and cook until golden brown on both sides.
Use slotted spoon or tongs to remove chicken from the pan, set aside. Lower the heat to medium low. Add chopped onions to the pan and sauté until translucent, stirring occasionally to release the browned bits from the bottom of the pan.
While onion is cooking: finely grind cooled walnuts in food processor. Add 1 cup pomegranate juice and 1/4 cup pomegranate molasses and process to make a fine paste. Add paste to onions in pot plus remaining pomemgranate juice and cook over low heat until mixture darkens and thickens, adding stock as necessary so it doesn't get too thick or burn. Takes about one hour and will resemble a Mexican mole when done.
Add saffron and taste and adjust for salt, pepper and molasses. Add chicken pieces and stock as needed to ensure they are submerged. Cook over low heat, at very gentle simmer until chicken is cooked through and falling apart.
Remove from heat and adjust sugar/salt to taste. Serve, over rice (if desired) garnished with pomegranate seeds, cilantro and a drizzle of pomegranate molasses.