At last count I believe I have over 60 different restaurants represented in my gallery serving pork tenderloin sandwiches. I'm just beginning to understand what makes a good one.
What I do know from others' comments and the email I get that most people fondly remember the one from their hometowns. Mug'n'Bun and the Igloo are two such fondly remembered tenderloins. But I think if so fondly remembered they do not realize they have changed. The Mug'n'Bun is a case in point that I know from first hand experience going back over 40 years. If not fondly remembered then it is just inexperience with the sandwich with no point of comparison. The sandwich no matter how good always seems to impress those that never had one. That appears to be the case with Dana with Mug'n'Bun and his recent foray into Indiana and Kentucky in another thread.
OK. Here is what I look for.
1. The restaurant itself. Character and history count. The overall atmosphere. The pride of ownership. Independents obviously get a nod over chains but there are not too many chains serving pork tenderloin sandwiches. Culver's serves a passable one as does the Machine Shed (a mini mini chain). Frisch's Big Boy restaurants serve pork fritters. McDonald's made an aborted attempt in Indiana a few years ago. I didn't have theirs but suspect it too might have been a pork fritter. Think chicken McNuggets to understand fritter. Mug'n'Bun serves a fritter.
2. The meat itself. There are true pork tenderloins and there are pork loins. In truth there is not a lot of difference in the taste if prepared right. The pork chop, the other cut of meat from the back of the hog is a bit chewier. The word tenderloin
seems to be a generic term for the sandwich. You can tell a true tenderloin if it has a distinct butterfly cut done so to make it big enough to over fill the bun. Pork tenderloins get a nod over pork loins but there are some mitigating balancers.
3. Meat quality. This one kind of puzzles me. I look for a moist tender cut that is white meat in character. So many are actually grey looking and they definitely do not taste as good. I'd like an explanation for the difference. My one suspicion is that the gray tenderloins tend to be the ones the restaurants that do not house prepare but probably get them pre-made from a distributor like SYSCO.
4. Meat preparation. This is the key to a great tenderloin. What makes Nick's Kitchen the best is because the pork marinates overnight in buttermilk and the resulting sandwich is a melt in your mouth sensation. I've done enough experimenting to know this is the one key difference whether it be a pork tenderloin or a pork loin. Most restaurants simply will not take this step. Tough, chewy meat is a turn off for me. Also if I encounter unchewable gristle then I know the meat wasn't trimmed properly.
5. Breading. I don't care for tenderloins that are dredged in flour only or in corn meal. That's OK for fish but not the breaded pork tenderloin sandwich. I'm not fond of the battered kind either but I have tried a few for comparison. I look for two things in breading. One it should have some taste. Salt and pepper could do it. Second I like crispy lightness. My preference is Panko Japanese bread crumbs but saltine crackers can do it as well.
6. Frying. This is a big variable depending on who is at the fryer or how fresh the oil is. The tenderloin should be fried hot enough so as to not soak up too much of the frying oil and feel and taste so greasy. The breading should be fairly dry of oil and should not peel away from the meat. Whoever fried my tenderloin at the Bourbon Street Distillery in Indianapolis completely blew it. It was an oily soggy mess with the breading falling off the meat and soaking the bun to the point you could not hold it. It should be fried to a golden brown. It takes about three minutes in a deep fryer and that is why the meat is pounded flat to 1/4" to 3/8" so the meat cooks through without burning the breading. Restaurants that try to serve a thicker sandwich generally cannot control the frying consistently.
7. Presentation. Many restaurants try to serve the biggest plate filling sandwich to where the bun becomes incidental. There should be an appreciable meat overhang for the traditional and visual effect. A good kaiser bun or bakery bun gets a nod over a plain hamburger bun. The restaurant should offer all the trimmings and condiments whether you want them or not. That would be pickle, onion, lettuce and tomato and either mustard or mayo. Good French fries or onion rings adds to the presentation. Those big plate filling sandwiches have to be pork loin. There is no way I know how to pound out a pork tenderloin to that size and still have some meat thickness. But that's OK. It is fun to have one occasionally like that if it is still prepared right and tastes good. Case in point. St. Olaf Tap in St. Olaf, Iowa had the largest I ever had at a full pound of meat but it was almost more fun to see fathers bringing their pre-teen sons in to try them for the first time. After all, it is the uniqueness and mystique of the sandwich that makes it so great.