Full disclosure, I do not like green bean casserole - it is too mushy and heavy for my liking. Consider this the anti-casserole green bean dish. It is like and crunchy and can be served at room temperate or warm.
Make ahead notes:
You can blanch the green beans up to 2 days in advance and keep covered in the refrigerator.
You can buy store bought crunchy shallots or onions to save time.