In a medium bowl, soak the chilies and raisins in 1 cup of hot water for 20 minutes. Drain and reserve.
In a large skillet, heat the oil over medium-high heat and brown the chicken until golden, about 3 to 4 minutes per side (do in two batches if necessary). Remove the chicken and pour off the oil. Place the skillet over medium-high heat and add the chicken, chilies, raisins, and all the remaining ingredients. Stir. Bring to a boil, reduce to a simmer, cover, and cook for 35 to 45 minutes, or until the chicken is cooked through, turning twice during cooking.
Remove the chicken from the skillet and cover to keep warm. Place the sauce in a blender or food processor and blend until smooth. Season to taste with salt and pepper. Pour the sauce over the chicken and garnish with additional sesame seeds. Serve with Toasted Corn Tortillas or plain white rice, if desired.