1 Dice potatoes (I like to keep the skins on for extra roughage and flavour, plus it means no peeling!), chop leeks and onion quite finely
2 Melt butter in large deep pan on low heat
3 Add veg, mix well with butter, cover and sweat on a low heat for 15 mins
4 Add milk, stock, herbs and S&P to pan, cover and simmer for 25 mins (be careful it doesn't boil over, milk can do that)
5 Let it cool for a few minutes and then blend veg to smoothish texture (tip: there is no need to put the liquid in the blender, just fish out veg with slotted spoon - or pass through a sieve if you don't have a blender)
6 Put puree back into pan with liquid, mix well and reheat, serve with a hunk of bread for dipping