ANSWER: This is, as several readers correctly guessed, a Bill & Bob's roast beef sandwich. Specifically, it is a Big Beef served "Three Way."
I also have to add something you might not be aware of — Bill & Bob's has blazing WiFi.
Thanks, everyone who guessed. Looks like I've got a lot of roast beef places to try around the city.
Each Saturday I'll post a photo of a dish from one of Salem's restaurants. In the comment section, make your guess about which restaurant served the meal. I'll circle back with the answer on Monday.
Take a look at this week's meal and Guess the Restaurant in the comment section. Good luck!