There are many regional varieties of serving hot dogs or sausage throughout the US, and the one I am the most fond of is a dying breed, even where it originated in northern New Jersey by Italian immigrants in the early 1930's. Don't let the proximity to NYC fool you, Newark style hot dogs are nothing like NYC hot dogs. Traditionally, a flat, round Italian bread made from a dough similar to pizza dough is cut in half and then opened up similar to a pita bread, but the pocket must be cut unlike a pita. This half would be used for a "double" or cut into quarters which are used for a "single". The grease which soaks into the bread is an essential part of the flavor of this classic. I would love for people across the country to give this a try and tell me what they think.
Traditional version -
Try to find some sort of Italian bread that isn't too crusty, that is flat and circular, maybe between 8" and 12" inches in diameter and an inch thick or so. If you are good with bread, bake something yourself, or possibly buy some pizza dough from a pizzeria and bake it in that shape. Cut it in half and then put a slit inside it to open it up similar to a pita bread. Spread the inside with a layer or your favorite mustard. Each half is for a double or can be cut in half again into two wedges for a single. Peel and slice some potatoes about 1/2" thick, then deep fry them in oil that isn't very hot until they become blonde (or blanch them). Cut slices of onion, red bell pepper, and green bell pepper (about an equal amount of onion to both types of peppers combines, but it doesnt have to be exact, I usually use one onion to one of each pepper). Sautee the peppers in some olive oil (or any oil) for a couple minutes until they start to soften and then add the onions, season with salt and pepper and optionally oregano and/or red pepper flakes. The goal is to get both the peppers and onions done at the same time and off the heat when they are perfect and not too soft. Crank the heat up on the oil (traditionally soybean oil is used) you used to fry the potatoes. Add the potatoes again, and then to the same oil, drop in either two hot dogs per double (one per single) or two precooked 4" - 5" lengths of italian sausage per double that are sliced in half lengthwise just until hitting the skin so they fan open but the two halves remain held together. The hot dogs should be fried until the skin rips open (or until the outside becomes crispy if using sausage) and the potatoes should be golden brown. Remove the dogs or sausauges with a slotted spoon, skimmer, spider or tongs and just shake off the excess oil, DON'T DRAIN, place them in the pocket bread (the hot dog should curve somwhat along the curve of the bottom of the inside of the bread). Then add the onions, peppers, and potatoes. Sprinkle the potatoes (and whatever else it lands on) with salt and pepper. Squirt some ketchup on top. As a general rule, I believe that for the most part, the mustard should be in contact with the hot dog, and ketchup in contact with potatoes. I don't care if it's all going to get mixed up in your mouth, ketchup doesn't belong directly on hot dogs! In Chicago, they will throw you out if you order a Chicago dog with ketchup... they won't do that in Jersey, but that doesn't change the fact that potatoes are the only reason that ketchup is invited to this wonderful creation. Wrap up the sandwich in foil leaving one end open and unwrap it as you eat it, as this is the least messy way to go about it.
Modern Versions -
You can replace the pocket bread with a Portuguese roll, sliced open normally (a large one is perfect size for a double).
Replace the potatoes with frozen crinkle cut french fries, or any kind of fries (as long as they aren't the real thin ones), which you won't have to fry the first time or blanch, just throw them in the oil with the dogs or sausage. You can use hot beef sausage (Caroline or Arnold's) instead of Italian sausage, which my personal favorite, as well as most of my friends. You can melt a slice of cheese onto the sausage too by placing it on top as soon as the sausage is out of the oil and then covering it with the hot onions, peppers, and potatoes. I usually use provolone or mozzarella with Italian sausage and American with beef sausage. A few dashed of hot sauce never hurt much either.
The only places I know of in Jersey that still serve traditional Newark style hot dogs are Jimmy Buff's and Dicky Dee's. Other than that, the modernized version is to be found on Greek owned lunch trucks, which is where I picked up the craft of making them as a 19 year old construction worker taking large coffee break orders aboard one and watching carefully. Even now as a culinary student intested in the finest Haute Cuisine, I have never lost my taste for one of these greasy belly busters, they always seem to hit the spot and I have friends who beg me to make them one once a craving hits them.
