This is a light and healthy recipe from Molly Stevens, printed in "Bon Appétit Magazine" (April 2008). In this delicately flavored main course, the asparagus steams along with the fish in individual paper packets. Feel free to tweak it to your preferences (substituting dill for tarragon, adding some garlic, etc). I like to add orange zest for more flavour. Recipe uses 4 15x15-inch squares parchment paper.