Potage Puree St. Germain

Place the peas in salted boiling water and blanche them for a couple of minutes once the water has come to the boil. Drain them and wash them in iced water so that they retain their colour. Soften the finely chopped onion in 1 tbsp butter, add the peas and mint and pour in the stock. Bring to the boil and simmer for 5-10 minutes before removing the mint. Puree the soup in a blender and strain it through a sieve. Pour the soup back into the pan and add the frozen butter portions. Season well and add a little sugar if necessary before heating through. Put 1 tbsp thick cream and croutons into each bowl and serve.