1) Peel the onion, parsnip and apple, removing the core from the apple, and chop into pieces.
2) In a soup pan warm the olive oil and add the chopped vegetables. Cook for about 5 minutes over a medium heat until slightly tender but not browned.
3) Add the stock cube to 1 litre of hot water, stir well, then pour into the vegetable pan.
4) Bring to the boil for 5 minutes, then turn the heat down to medium and simmer for about 10-15 minutes, until the vegetables are soft.
5) Season with salt and pepper and pour the soup into a blender. Blend until completely smooth. If the soup is too thick add a bit of water to thin it out.
6) Pour the soup back into the pan, stir in the heavy cream and heat until hot.
7) Serve with a nice piece of crusty bread.