In a large pot heat the oil, add the vegetables and ginger, give a sprinkle of salt. Gently sauté for 5 mins until the vegetables begin to soften but not brown.
Add the stock and the half the lemon and simmer for 20 mins.
Once cooked, remove the lemon half and blend the soup until silky and smooth.
Stir through the cream and season with salt and white pepper to taste.
When ready to serve, gentle reheat. Serve topped with a squeeze of lemon, a sprinkle of chopped chives and a garnish of parsnip crisps.