- Melt the butter in a large pan over a medium heat.
- Add the onions and sauté until translucent.
- Add the watercress (reserving some leaves for garnish), the milk and approximately 700ml (1¼ pints) of water to the pan and bring to the boil.
- Once boiled, remove from the heat.
- Ladle the mixture from the saucepan into a food processor and liquidise until smooth. Season with salt and pepper.
- Peel the pear, take out the core and cut into fine strips. In a bowl, mix the pear strips with the lemon juice and sugar.
- Serve the soup either hot or cold, and garnish with the peas, dressed Asian pear and a few watercress leaves.