Melt butter over medium heat.
Whish in flour, salt and pepper. Cook for 1 minutes.
Add milk. Cook, stirring continually, until sauce thickens.
Place asparagus in 9x13 inch baking dish. Top with shredded cheese. Pour thickened sauce over asparagus and cheese.
Toss breadcrumbs with melted butter and sprinkle on top of vegetable.
Bake for 20-25 minutes, until breadcrumbs are golden brown.