CRÈME D’ASPERGES is also known as crème Argenteuil in honor of the region (in north central France) where the best asparagus are grown. (In fact, any dish that includes the name Argenteuil contains asparagus.) What made this a “cream” soup in the classic kitchen was that it was made with a light béchamel, though the rules were often bent to make it with a thickened stock (velouté) or a combination of the two. I find the flavor better when made with stock alone (and even better if made with veal stock). This recipe produces a very light and delicately creamy soup, but for those who prefer theirs thicker or more creamy, it is an easy matter to add up to another tablespoon of arrowroot or double the cream. The soup can also be thickened by using a small potato instead of the starch. Finely dice the potato and add at the same time as the asparagus.