Onion sauce: Heat the oil in a medium saucepan over medium heat. Add the onions and saute until they are soft. Stir in the honey, cinnamon and chili powder and cook for 1 minute. Add the ketchup, water, hot sauce, salt and black pepper. Bring to a simmer and cook until the sauce thickens, about 10 to 15 minutes. Transfer the mixture to a bowl and let it cool to room temperature before serving. (Chef's Note: The sauce can be refrigerated, covered, for up to 2 days.)
Assembly: Put the boiled hot dogs onto the buns. Spread the bottom half of each bun with some mustard and top each hot dog with the onion sauce or sauerkraut or both.