I grew up in Japan, England and the U.S., so all the good and bad of the food culture of each country is part of my food vocabulary. While I like to try out new things as much as any enthusiastic cook. "comfort food" to me means things that I used to eat when I was little.
The British have a penchant for the most wonderfully stodgy food. A fishfinger buttie is one such thing. I honestly don't know if this thing would taste good to anyone except someone who's grown up eating it. Jamie Oliver even has a recipe for it in one of his cookbooks (I can't remember which...it could be Happy Days). It's basically a white bread sandwich with yes, fish fingers or fish sticks - those breaded frozen things with dubious fish (they usually say cod) inside, that you either bake in the oven or fry up in a pan - as the filling. Sounds awful? Maybe, but it is a tasty snack sometimes. For some reason I like this only in the cold months...I never get a fishfinger buttie craving in the summer.
My version of a fishfinger buttie
For 1 buttie (sandwich):
Prepare the fish fingers, either by baking in the oven or toaster oven, or frying them in a bit of butter in a frying pan. If you do this drain them well on paper towels. Do not microwave the fish fingers. Sure it's just snack food, but you don't want soggy fingers!
The bread should be fresh and good. A nice crusty bread is nice, but regular loaf bread would do too. The slices should be pretty thick.
Spread each slice of bread with some mayonnaise. Put the fish fingers on one. Drizzle the Worcestershire sauce or (preferred) thick steak sauce over the fish fingers. Cover with a couple of iceberg lettuce leaves, then the other slice of bread.
Eat with milk or a good bottle of beer.