1. Steam broccoli 5 minutes or until crisp-tender; drain. Pat dry, and keep warm. Cook pasta in boiling water in a large saucepan for 8 minutes or until al dente; drain and keep warm. Wipe pan with paper towels, and return to medium heat. Melt butter in pan. Sprinkle flour over melted butter; cook for 1 minute, stirring constantly with a whisk. Gradually add milk to the flour mixture in pan, and bring to a boil, stirring constantly with a whisk. Cook for 1 minute or until slightly thick, and remove from heat. Add American cheese; stir until smooth. Stir in sliced green onions and the remaining ingredients. Stir in broccoli and pasta; serve immediately.