For the Pozole, place pork in 5-quart Dutch oven. Add stock, oregano and bay leaves. Bring to boil on high heat, skimming any foam from surface. Reduce heat to medium-low; cover and simmer 1 1/2 hours or until pork is tender.
Meanwhile, for the Arbol-Ancho Chile Sauce, soak chilies in 1 cup boiling water in covered medium bowl 30 minutes or until softened. Remove chilies with kitchen tongs to blender container. Add 1/2 cup chile soaking liquid, onion, ancho chile pepper, garlic salt, cumin and allspice; cover. Blend on high speed until smooth. Set aside.
Transfer pork to large bowl, reserving stock in pan. Coarsely shred pork using 2 forks. Return pork to stock. Stir in hominy and 1/2 of the Chile Sauce. Bring to boil. Reduce heat to medium-low; cover and simmer 30 minutes to blend flavors.
Ladle pozole in bowls. Serve with remaining Chile Sauce, desired toppings and additional oregano for sprinkling.