About the cider vinegar in the devilled eggs -- almost enough to taste; it mostly cuts the richness. Can't give you exact amounts since I don't measure; I come from the "hurl in a goodly handful" school of cookery.
Try stirring about half a cup of diced gruyere cheese into the mix when you make the traditional green bean casserole. Adds another dimension of flavor -- plus another assault on your arteries! This also works beautifully with fresh asparagus cut into chunks -- a variant on a 15th-century recipe for "savoury toasted cheese". And those Durkee onions are french-fried after being dipped in a batter, something you CAN do yourself but somehow more traditional (midwestern?) out of the can. The batter adds something to the finished dish toasted breadcrumbs + regular browned onions can't match.
(Did you know that macaroni and cheese is medieval? I have a 13-century English recipe for "lozenges" which is dough rolled thin and cut into diamond shapes, boiled, then layered with white cheese and a bit of nutmeg. White lasagna anyone? I also found an early reference to elbow macaroni or quill pasta, from 15th-century Italy -- it talks about taking dough about the thickness of a straw and rolling it around an iron rod the thickness of a cord. This is then dried, and the book says it keeps about three years this way.)
I also make an easy apple pie with cranberries -- stir a can of whole-berry cranberry sauce (cut into dice) plus some cinnamon into about four Granny Smith or York apples peeled and cut into thin slices. Add a cup of vanilla yoghurt if you like, and/or an handful of broken pecans. Pour this into a crust and bake until bubbly.
MY SO made another traditional dish today for lunch -- oyster stew. He is from Hadley Mass and makes his very plain -- oysters, butter, cream and oyster crackers with a bit of salt and pepper, that's it. Me being from upstate New York, mine is fussier -- onions browned with bacon, shredded carrot, and celery, cream, oysters, and a bit of sherry. Almost New England chowder.