Slice the cardamom pods, open. Combine cardamom, cloves, star anise, cinnamon stick, anise seeds and coriander seeds. Use a large square of double thickness of cheesecloth, place the spice mixture in the middle. Fold up the sides, forming a pouch. Tie the top closed using thread or a piece of culinary string. Add red wine and the spice bag to a large non-reactive pan. Gently heat just to the boil, reduce heat to low and add orange slices.

Cook this for an additional 15 minutes.

Remove spice bag, sweeten with sugar to taste.