Cook asparagus according to package directions; drain.
Toast bread on one side.
Mix together the lobster, 1/3 cup mayonnaise, celery, and pimiento.
Spread mixture over untoasted side of bread.
Sprinkle shredded cheese over each; arrange asparagus on each sandwich.
Beat egg yolks, 1/4 teaspoon salt, and dash pepper till thick and lemon-colored; stir in the 1/4 cup mayonnaise.
Fold into egg whites.
Pile mixture atop asparagus.
Bake at 350Â° till topping mixture is golden brown, about 18 minutes.