Heat the oil in a large pot over medium-high heat. Add the chicken and cook until browned on both sides, about 5-7 minutes per side. Remove the chicken from the pot and set aside.

In the same pot, add the chopped onion and saute until soft and translucent, about 5 minutes.

Add the ground walnuts to the pot and stir continuously for about 5 minutes until it becomes fragrant and slightly darkened.

Add the pomegranate juice, sugar, salt, and pepper to the pot and stir to combine.

Return the chicken to the pot and bring the mixture to a boil. Reduce the heat to low, cover the pot, and simmer for about 1 hour or until the chicken is cooked through and the sauce has thickened.

Taste the sauce and adjust the seasoning as needed.

Serve the Persian Chicken Stew hot with rice and garnish with pomegranate seeds and chopped herbs, if desired.