I received a copy of your recipe a few years ago and while it is very good, it wasn't quite the same as the restaurant I visited often when I lived in New York. In my quest to determine the ingredients I had a sample of the sauce analyzed by a master chef and he determined the following:
<Master Chef Notes>
The list of spices used in this sample sauce recipe are....
Grease from food preparation
Onion Dehydrated - Ground
* Ginger Root - Ground
* Bay Powder - Fragmented Leaf Powder
* Celery Seed ( or similar ) - Ground Fine
* Black Pepper - Coarse Grind
* Turmeric - Ground
* Nutmeg - Ground
* Coriander - Powder
* Cloves - Powder
* Fenugree -Powder
* Red Peppers (probably shredded)
* Cumin flakes (probably shredded)
** Citric Acid
* These spices are all found in McCormicks Curry seasoning
** The local restaurant sells Sunny D'Light
The spices are probably a mild curry mix available through a Greek grocer with the above ingredients. This is probably a good starting point.
The sauce probably is made from leftovers in the kitchen with spices and a thickening agent is used (probably flour). It appears to be more gravy like than chili. So the guess is it starts out as a roux of equal parts of leftover grease from the hamburgers and hot dog preparations and flour. Once the roux has cooked to a light brown, the the spices are added and the roux is allowed to absorbed the flavors for two to three minutes before water and OJ are added.
There appears to be more cloves than what is found in the typical curry mixes.
</Master Chef Notes>
I checked local grocers (not Greek) in the area and discovered that all of these ingredients are found in McCormicks Curry mix. The citric acid probably comes from orange juice or in the case of this particular restaurant, Sunny D'Light.
If I were to guess the recipe goes something like this:
Prepare a light to medium brown Roux using the following:
1/2 Cup of lard (restaurant uses grease drippings with beef particles from food preparation)
1/2 Cup of flour
When Roux is at the desired color, remove from heat and add the following seasonings:
2-3 TSP of Curry powder
1-2 TSP of Cloves powder
Allow the Roux to absorb the seasoning's flavors for 2-4 minutes then add the liquids and hot dogs grounds
4-6 Grilled hot dogs (processed with a food processor or finely chopped as the restaurant probably uses leftover dogs)
8 Cups of water
1/2 Cup of Sunny D'Light or OJ
Return to heat and bring to near boiling and keep stirring so the mixture does not stick to the bottom of the pan and until the consistency of a light gravy is achieved. Taste along the way, adjusting the seasoning, salt or pepper as you like it.