How to Make It
In a heavy saucepan, bring the stock to a slow, steady simmer over moderate heat. Lower the heat and maintain the simmer.
Cut the asparagus tips to 1-inch and set aside. Cut the remaining asparagus into 1/2-inch pieces.
Trim the stems from the morels and reserve them for another use (in stocks or soups). Brush any debris from the morels and, if they are very large, cut them in half.
Heat the oil and butter in a heavy-bottomed, broad, medium saucepan over moderately-high heat. Stir in the onions and sauté for about 5 minutes, or until translucent. Add the asparagus stalks and the morels and sauté for about 1 minute, or until they are well-coated with the fat. Add the rice and sauté for a few minutes to thoroughly coat the grains with the fat.
Add 1 cup of the simmering stock and cook, stirring constantly with a wooden spoon, until all of the liquid has been absorbed by the rice, about 5 minutes. As each addition is absorbed, continue stirring and adding stock, 1/2 cup at a time, until the rice is tender but still al dente. You should begin tasting the rice after it has cooked for about 20 minutes. Just before the rice is ready, stir in the reserved asparagus tips, 1/2 cup of the cheese and the parsley. Season with salt and pepper.