Preheat oven to 325
Saute onion in butter until translucent
Cook egg noodles per instructions
Mix cooked egg noodles, drained noodles, drained peas, onion, soup, milk, 1 cup cheese and seasoning
Pour into 9x13 greased baking dish.
Top with 1 cup of cheese and saltines.
Cover with foil and cook for 20 minutes. Uncover and cook for 10 more minutes.