1. made by yourself at home
i really really like cheddar cheese(pref cathedral city or other decent medium/mature cheddar), smoked ham and cucumber sandwiches. butter/spread on one slice, then cheese, then ham the cucumber laying on a slice spread with light mayo.
not saying that's the best/my favourite sandiwch but it's pretty great. thinking of my favourite ever sandwich filling/s is going to take a bit more thought, it's a pretty intense question.
egg and cress is pretty yummy, got to be well salted too