Asparagus Casserole

2-14.5 oz cans cut asparagus,  drained or 4 cups fresh asparagus cut into ½” pieces
1 1/2 T butter, melted
1 T flour
3/4 C milk
2/3 C cheddar cheese, grated
1/8 tsp salt
1/2 C Ritz crackers, crushed
1/2 T butter

Preheat oven to 325 degrees.  Place cut asparagus in casserole dish.  In small pan over medium heat, melt butter.  Add flour, then add milk gradually.  Cook slowly until thickened, stirring constantly.  Add cheese and salt.  Pour sauce over asparagus, sprinkle with cracker crumbs and dot over top with butter.  Bake 40 minutes.