Watercress and spare ribs soup (西洋菜排骨汤）

Ingredients
250g watercress
250g spare ribs
5 slices old ginger
1/2 tbsp salt
1 tbsp light soya sauce
dash of pepper


Prepartion
1. Boil 1.2 litre water in a pot.
2. When the water boils, add in the ginger, spare ribs and cover to boil for 5 minutes.
3. Add in the watercress and cook the soup over medium flame for 30-45 minutes.
4. Put in salt, light soya sauce and pepper to taste.
5. Serve hot.