I recall (vaguely) having Christmas dinner at my grandparents small home. They had a large room in the basement with a big dinner table set up in it. I only recall it being used at Christmas. Cramped and dimly lit.
And there was lutefisk. I don’t recall ever eating it. All of my grandparents came from Norway. My sister (still in Minnesota) was going to a friend’s house soon for a lutefisk dinner. She said the friend uses a good cream sauce (with cheese??) that she likes.
I recall hearing something about Grav-loks. Fish (salmon?) that is buried (grave - I suppose for storage in the cool earth??).
Gravlax is cured salmon, sliced thin and usually served with a little mustard sauce. Traditional lox is similar, neither are smoked.