I have made many "Dagwood" sandwiches. My recipe is very similar: Multiple slices of any type of sliced bread slathered with mustard and/or mayo. Multiple slices of any type of sliced meats and cheeses. Add healthy portions of lettuce, tomato, onions, pickles and sliced green pepper. Throw in a couple of olives and eat.
I started making these when my now grown sons were pre-teens and we would compete to see who could make the tallest and most outlandish sandwich!