Cook asparagus according to package directions; drain well. Set aside.
In a medium saucepan cook mushrooms and onion in margarine until onion is tender but not brown. Stir in cornstarch, salt, nutmeg, and pepper. Stir in milk all at once. Cook and stir until thickened and bubbly. Cook and stir for 1 minute more. Stir in crab and asparagus.
Spoon mixture into four individual casseroles.
In a small bowl stir together almonds and Parmesan cheese. Sprinkle atop casseroles.
Bake in a 400 degree F oven for 10 minutes or until mixture is heated through and cheese is browned. Makes 4 servings.