1. Only beneath the blue and yellow umbrella shall you eat.
2. A hot dog shall be eaten on the street, no matter what your Nonna said.
3. You shall garnish your hot dog with mustard, or with relish, or with onions, or with kraut, or All the Way.
4. Ketchup shall be an abomination unto you, ye shall not eat of it.
5. You shall not complain about the price: it is New York.
6. The water is not dirty, it is hot dog juice.
7. The skin of a hot dog has a pleasing snap, but ask not what lies beneath.
8. You shall never visit a hot dog factory, lest you lift up your heel against hot dogs forevermore. You do not want to know how they are made.
9. Remember St. Papalexis, for he is holy.
10. A hot dog tastes best at Yankee Stadium, even if it is Nathan’s Famous and not Sabrett. But then, anything tastes good after 10 beers.

Stolen shamelessly from the Huffington Post:

Sabrett-style Onion Sauce Recipe

Makes. 4 hot dogs
Preparation time. 1 hour

Onion Sauce Ingredients
1/2 cup water
1 teaspoon cornstarch or arrowroot
1 tablespoon tomato paste
1 tablespoon inexpensive balsamic vinegar
1 teaspoon Dijon-style mustard
1 teaspoon brown sugar
1/4 teaspoon hot pepper sauce
1 pinch of cinnamon

1 tablespoon olive oil
2 large red onions, peeled thoroughly and sliced thin
1/4 teapoon table salt
2 cloves of pressed or minced garlic

About the onions. Red onions often have an extra layer of tough paper under the outer layer. Make sure you remove it.

About the tomato paste. If you want, you can substitute a 2 tablespoons of ketchup or a sweet tomato based Kansas City style barbecue sauce for the tomato paste.

The hot dog
4 all-beef frankfurters, preferably Sabretts
4 buns
Sauerkraut from the refrigerator section, not the can
Spicy brown Dijon-style mustard

Do this

1. Combine the water and cornstarch in a bowl and whisk it until there are no more lumps. whisk in the tomato paste, balsamic, mustard, brown sugar, hot sauce, and cinnamon.
2. Warm the oil in a large skillet, not a non-stick, over medium high heat. Add the onions and sprinkle with the salt. This helps pull the moisture out. Move them around occasionally with a wooden spoon so they don’t burn. Cook until the edges start to brown. Whatever you do, do not let them burn. Add the garlic and cook for another minute.
3. Add the liquid, stir, and rub the pan with the wooden spoon to scrape up all the flavorful fond, the brown bits on the bottom. Turn the stove to low and simmer with the lid on for 1 hour. Check frequently to make sure it is not burning and the water has not evaporated. Add water if needed. The final result should be thick, not runny, but not pasty. After an hour, taste and adjust salt and other flavors as you wish.
4. While the onions are simmering, warm the kraut in a pan or for 15 seconds in the microwave, cook the franks, and prepare the buns. The franks can be cooked on a griddle, on a grill, but most pushcarts make “dirty water dogs” by simmering them in water that has become a rich flavorful soup after holding scores of franks over the course of a day. And don’t worry, the franks are precooked so they are pasteurized, and the dirty water is hot enough that nothing can survive. As for the buns, some are toasted on a griddle, but most pushcarts store them in a bin where the steam from the dirty water keeps them warm and moist.
5. Lovingly place the frank on the bun, squirt on the mustard, add the onions, and then the kraut. Hum quietly, I’ll take Manhattan…

The Old Wolf has spoken.