Slice onion. Cut leek length-ways and rinse thoroughly to remove all dirt between the layers, then slice. Next peel and dice potatoes.

Add onion and leeks to a pot with a little oil. Add potatoes and cook for a few minutes to soften the onion.

Add your water and crumble in your stock cube. Bring to a boil and simmer for 15 minutes till the vegetables are tender.

Season to taste and blend to a smooth consistency. Add your creme fraiche and stir through to make a creamy soup. Traditionally you can use double cream, depending on personal taste but both will make it creamy.

Serve with crusty fresh bread and butter.