The best things are those that pass the test of time. And that is particularly true of food. There are so many fads that come and go, but the best things stick around. At Chelmsford Sub Shoppe, we are proud to bring you the timeless meals that never wane in popularity. It’s impossible to pick a favorite, but roast beef sandwiches are definitely near the top of our list. But how much do you know about this New England staple?