Place corn in enough unsalted cold water to cover. Heat to boiling. Boil uncovered 2 minutes; remove from heat. Cut enough kernels from ears to measure 2 cups.
Heat oven to 350. Heat 2 tbsp butter in saucepan over medium heat. Cook onion and bell pepper in butter for about 2 minutes, stirring occasionally until onion is tender; remove from heat. Stir in flour, salt, paprika, mustard and pepper.
Cook, stirring constantly until mixture is bubbly; remove from heat. Gradually stir in milk. Heat to boiling, stirring constantly. Boil and stir for 1 minute. Stir in corn and egg. Pour into ungreased 1 quart casserole.
Mix crumbs and 1 tbsp melted butter. Sprinkle over corn mixture. Bake uncovered for 30-35 minutes or until bubbly.