In a saucepan, melt 2 tablespoons butter; stir in flour until smooth. Gradually add milk. Bring to a boil over medium heat; cook and stir for 2 minutes. Remove from the heat; stir in cheese and salt until cheese is melted.
Add the ham, noodles and peas. Pour into a greased 1-qt. baking dish. Melt remaining butter; add bread crumbs and parsley. Sprinkle over casserole.
Bake, uncovered, at 350° for 30 minutes or until heated through.