3: Pour 3 tablespoons olive oil into a large pan on medium heat. When good and hot add the sliced onion. Salt, pepper and cook for 1 or 2 minutes without colouring.
4: Add the sliced artichokes, mix well and leave to cook gently for 2 or 3 minutes.
8: Check the seasoning and your soup is ready. Serve as it is or garnished with morsels of lightly fried ham.
Remarks
The vegetables are cooked in two stages: the Jerusalem artichokes are simmered on their own first, as they take much longer to cook than the leeks. This allows us to cook the leeks until just done and keep their lovely green colour in the finished soup.