Heat the oven to 320F. Put the ribs, fleshy side down, in a single layer in a large roasting tin. Pour over the Dr Pepper and add the spices. Tightly cover with foil and cook for 2 hours.
Put all the glaze ingredients in a pan and simmer until thick and syrupy.
After the initial cooking take the ribs from the oven and turn it up to 390F, or light your barbecue. Drain all the liquid from the tin. Turn the ribs flesh side up and baste with the glaze. Roast for 30 minutes or barbecue, adding more glaze halfway through until sticky and shiny. Cut into sections to serve.