Cut parsnips and pears into large pieces. Place on a lined baking tray or roasting pan, and bake for 45 mins or until golden brown, turning half way through.
Add the peeled chestnuts and roasted parsnip and pear to a large pot with the thyme, stock and lemon juice and simmer 30 mins.
Allow to cool slightly, and then puree the cooked soup in a blender until smooth (you may need to do this in batches). Add the extra water as needed (this will depend on how thick/thin you want the soup - omit if you want a really thick, hearty soup).
To make the caramalised pear topping, heat a fry pan over medium to high heat and add a little oil or butter. Add the diced pear and cook until golden brown on all sides, around 5 minutes
Recipe by to her core at https://tohercore.com/roasted-parsnip-pear-and-chestnut-soup/