Wash the leeks to remove dust and soil, remove ends from both sides and chop in small pieces. Wash, clean and cut the potatoes and carrots in
pieces. Put the leeks in a saucepan and saute with butter. Add corn flour, the cube of stock, potatoes, carrots and 3
cups of water. Stir well and simmer until vegetables are tender. Serve hot. If you want you can mash the vegetables in
with a blender to make the soup smooth.