Boil celery in water to cover for about 10 minutes or until tender. Drain.
Melt 2 tablespoons butter over medium heat.
Stir in flour and add milk slowly, stirring constantly until thick and smooth.
Add salt and drained celery.
Spoon mixture into greased 1 1/2 quart casserole.
Top with pecans (or mix in with celery mixture).
Mix bread crumbs with 1 tablespoon melted butter and sprinkle over celery mixture. (Can refrigerate, then bring to room temperature and bake.)
Bake uncovered at 400 degrees for 15 minutes.