Remove the rind from the asparagus with a potato-peeler. Cut the tips at about 0,8 inch and put aside. Boil the asparagus stalks in just a little salted water. Filter the cooking liquid. Take the tips, to be kept whole. Puree the asparagus stalks and put the pulp into the stock. Peel the scampi. With the heads and the shells make a stock with water, carrot, half an onion, celery and a bay leaf. Filter the stock and add it to that of the asparagus. Toss the asparagus tips for a few minutes in 2 Tbsp of butter. Brown in a pot in oil the rest of the onion and the chopped garlic. Brown the scampi tails. Add wine, parsley and cognac. Allow to evaporate. Add the asparagus tips and the rice. Finish off cooking together with the fish stock and asparagus. Adjust the salt and pepper. Towards the end of cooking, cream with the butter and Parmesan.