Start by chopping the carrots, parsnip and potato. Trim, wash and chop the leek, peel and chop the onion, and core and chop the apple. Peel and crush the garlic.
Throw the veg and apple into a large pan with the garlic and a good lug of oil and mix it all up. Season to taste (minimally, if cooking for young children).
Cook on a medium heat for 10 minutes, stirring occasionally, or till the veg start to soften. Add 2 litres of water to the pan, bring to the boil, then turn down to a simmer. Cook for 30 minutes, until all the veg are soft.
Blitz with a hand blender until smooth, then sprinkle with sweet paprika. Delicious served with buttered toast.