I've researched condiment recipes as much as I can. These types of recipes are closely guarded secrets. Think Coca-Cola. They don't want a copy of that getting out.
I've always wanted to make my own chile sauce. Pardon the other writer's misspelling, as it should not be chili.
Some while ago, I had found a cookbook author, one Gisine Lemcke, who ran a cooking school in Brooklyn NY in the late 19th early 20th century.
Below is her recipe. It's use of green tomatoes will impart that slight tang that chile sauce has, and that ketchup does not have. Heinz Chili Sauce sells at a premium to Heinz Ketchup. Now you know why.
Preserving and Pickling
By Gesine Lemcke
New York: Appleton, 1919
https://www.google.com/books/edition/Preserving_and_Pickling/08pDAQAAMAAJ?hl=en&gbpv=1
Chili Sauce No 1
24 ripe tomatoes
15 green tomatoes
4 large onions
3 green peppers
4 tablespoonfuls of salt
2 tablespoonfuls sugar
1 quart of vinegar
1-2 tsp. cloves
1-2 tsp. allspice
1-2 tsp. ginger
1-2 tsp. cinnamon
Scald and free the ripe tomatoes from their skin and cut them in small pieces. Cut also the green tomatoes, the peeled onions and the green peppers, put all the ingredients in a kettle boil slowly 1 2 hours.
Mrs. Lemcke, does not describe more than the above. Maybe this will cook to the correct consistency and not need a milling, but keep that in mind. Some bits are acceptable. I imagine Heinz removes the seeds from theirs as that would impart a bitter note.
If preserving with sodium benzoate, remember not more than .1%, that is .001 by weight. Add the benzoate after cooking, but before the pot reaches room temperature.