- With the rack in the middle position, preheat the oven to 180 °C (350 °F). Butter a 28 x 18-cm (11 x 7-inch) baking dish.
- In a pot of salted boiling water, blanch the asparagus for about 3 minutes. Drain and place the asparagus in the buttered dish. Set aside.
- In a saucepan, melt the butter. Sprinkle with the flour and cook for 1 minute. Add the milk and bring to a boil, stirring constantly with a whisk. Remove the pan from the heat and add half the cheese and the nutmeg. Stir until the cheese has melted. Season with salt and pepper.
- Pour the béchamel sauce over the asparagus. Sprinkle with the remaining cheese. Sprinkle with the breadcrumbs. Bake for about 35 minutes or until the asparagus are tender. Serve with grilled fish or meat.