"There are many ways to skin a cat and many more ways to cook a dog." Meathead
Char Dogs on the Grill
The franks at above are before and after at Ted's Hot Dogs in Tonawanda, NY, near Buffalo. They still cook them on a grill, and if you ask, they'll char them til the split open. They taste mighty good this way despite the fact that a lot of juices and flavors drip out.
Me? I like to keep them from splitting and blackening. I think the best flavors happen when franks are crunchy dark brown, just this side of black. Here's how to do it.
Preheat the grill to medium high and set up a 2-zone cooking area. If the franks are curved, bend them gently in order to flatten them out a bit. This will make it easier for you to roll them around and cook them evenly on all sides.
Now this may seem crazy at first, but think about it: Put them on the grill running parallel to the grates so they nestle nicely between two yard markers on the gridiron (yes, a grill grate is properly called a gridiron and has been since before football was invented). Now they won't get those nice horizontal stripes this way, they'll get vertical stripes, but when they have a nice dark brown char, but not a black burn, just roll them over the grid into the gap between the next two grids, and repeat until all sides are done. This way you get more caramelization and the Maillard reaction that develops flavor in the meat when it turns brown. People will laugh at first, but when you explain, they'll elect you mayor.
Cook over a medium heat. They will take a bit longer, but they wont split open. If you're in a hurry, you can crank up the temp, but stay near the grill so they don't burn.
Finally, here's a trick I learned from Gold Coast Dogs in Chicago: Cut an X shape in the ends of the dog. When they cook they will curl up and get extra crispy (see photo). Cook the dogs over a medium high grill until the skin darkens and there are nice grill marks all around.
Char Dogs on the Griddle
OK, let's get some terminology straight. Those cast iron flattop or flatiron "grills" are just not grills. They are griddles. Just don't tell this to the short order cook behind the counter unless you want to get thrown outta the joint. But he's not really grilling. He's griddling. Grilling is done on a gridiron over an open flame. Griddling is cooking in a thin layer or oil on a hot flat surface, usually cast iron or cast aluminum. And there's nothing wrong with it. It's a great way to develop flavor. Many of the world's best hot dog joints cook on a flattop. You can do it indoors or out with a good cast iron frying pan or griddle if you have one. In fact, I've been known to take my cast iron griddle or frying pan an put it on my grill for hot dogs and other things (like fish).
Make sure the surface is clean, and lay down a thin coat of vegetable oil, shortening, or lard. Go crazy and use bacon grease if you want. Just keep the heat down to medium or medium high. Animal fats burn at high temps.
Do not bend the franks straight. Lie them all down facing the same direction. When they get dark brown, flip them all. When the second side is browned, ring the dinner bell.
The idea here is to create maximum surface area to brown so we split the dog in half langthwise, leaving a small hinge on one side so it is still one piece not two. This is especially useful if you want to stuff the dog with cheese and wrap it with bacon, then deep fry it. Hmmmmm.
Dirty Water Dogs
Let's clarify terms right at the top. There is nothing dirty or unsafe about this method. It get's its name because, in a production environment like a restaurant or streetcart, the water will get cloudy with extract from previously cooked dogs. This is good, not bad. The advantage is that natural casings stay snappy, but don't get tough. The salt in the dogs pulls in water by osmosis, swelling the girth and making very juicy dogs that practically squirt when you pierce them with your incissors. You can also keep franks in the water for hours and they don't deteriorate significantly, although some flavor will migrate into the water. The secret is to use enough water to cover the dogs, but not too much.
Here's how. In a sauce pan pour enough water to cover the franks you need to cook. Bring the water to a boil and add the franks. This will knock the temp back a bit so it should stop boiling, but dial the temp down to just above low so the water simmers gently. You do not want to boil a frankfurter, especially a frank with a natural casing because it can split open and spill its guts or some of its juices and flavor. Simmer for 10 minutes. If you don't plan to use them right away, you can keep them in water for hours safely as long as the temp is over 160°F.
As with dirty water dogs, steaming plumps and moisturizes franks. But there is much less flavor leakage into the water. A very worthy alternative surprisingly rare in the real world. May I recommend it to yours?
Just drag out your regular veggie steamer, metal or bamboo, charge it with water and bring it to a boil, and steam the meat for about 15 minutes. Simple. Delicious.
Purists may frown, but microwaves were practically built for frankfurters. They vibrate the molecules in the center getting them excited, and that gets them hot and bothereed. No fluids are lost or gained, no surfaces are burned. And it all happens on high in about 2-3 minutes, depending on the thickness of the dog. In Joisey they say, badda bing, badda boom. All done.
A few joints deep fry their dogs in vegetable oil until they split open. Rutt's Hut in Clifton, NJ, is the best known. Their "Rippers" are crunchy on the outside, chewy near the surface, and tender on the inside. If you have enough oil, you can do it too. Maybe that's what you can do with the leftover oil from the time you tried to deep fry a turkey...