Poach the ribs in a pan of boiling water with the sliced ginger and leek (or spring onion) for about 2 minutes.
Place the ribs onto a wire rack on a baking sheet in the oven and cook for 30 minutes.
In the meantime, bring the Coca Cola, soy sauce, the rest of the sliced ginger, sugar and mild chilli spice up to the boil in a frying pan and reduce the sauce until about half the original amount remains.
As soon as you take the ribs out of the oven, put them in the sauce which must be hot, and turn them over several times until the ribs are coated all over. Continue to cook until the ribs have absorbed most of the sauce.