1Fry the rashers of bacon in the oil until crisp. Set aside for later.
3Add the onion and garlic to the pan, stirring until tender, then add the parsnips. Cook for another 5 mins, then crumble in the chicken stock.
5Add the milk, 600ml water, the thyme and chestnuts. Cover and simmer for 30 mins until the parsnip is tender.
7Blend with a hand blender, then season to taste.
9Serve the crispy bacon on the top.