Non packaged Mac and Cheese

I havent used a packaged mac and cheese for 30 years. My grandson ate my homemade mac and cheese and now he doesn't like packaged mac and cheese.

White sauce is real easy to make.

In medium pot add 4 tbls butter, add onions if you put onions in your mac and cheese. When melted add 4 tbls flour and stir. It gets real pasty. Add 2C milk. Stir until thickened. If it is still two thick add more milk. If it needs thickening combine a tablespoon butter and tablespoon flour and add to mixture. This way it won't lump. Add salt and pepper to taste.
Add 1C grated cheese of your choice. More if you like with more cheese.
Grease 9x11x glass baking dish or any dish it will fit in.
Cook @ 350 degrees for 45 minutes with foil on top. Take foil off and cook for 10 minutes more if you like the top crunchy.