1: Prepare 4 leeks, but keep the white part whole (don't split or chop them) then slice them about 2 cm or 1 inch thick. Cut on the diagonal as this looks nicer (see photo).
2: Steam the leeks in a pressure cooker for five minutes, counting from when it starts to hiss.
3: The idea is to have leeks which ar only just cooked and which keep as much of their colour as possible.