First off lets examine the ingredients below as listed on the little packets of the sauce itself.
SECRET SAUCE Water, soybean oil, tomato paste, high fructose corn syrup, mustard (water, distilled vinegar, mustard seed, salt, turmeric, spices), distilled vinegar, dehydrated onion, egg yolk, salt, contains less than 2% of the following, A-1® Steak Sauce (water, distilled vinegar, tomato paste, corn syrup, raisins, salt, herbs and spices, orange base, orange peel, dehydrated garlic, caramel color, dehydrated onion), xanthan gum, Tabasco® Sauce (vinegar, red pepper, salt), sodium benzoate and potassium sorbate as preservatives, spices, Worcestershire® Sauce (distilled vinegar, molasses, corn syrup, water, salt, caramel color, garlic sugar, spices, tamarind, natural flavor and sulfiting agents), natural flavor, oleoresin paprika.
The first five ingredients Water, soybean oil, tomato paste, high fructose corn syrup sound really familiar together. Yup you guessed it –that’s ketchup (minus vinegar, onion powder, salt, and spice). They spell out mustard next. Then is vinegar–that belongs to ketchup. Now comes dehydrated onion which is typical in many of the fast food burger chains. Next ingredient- egg yolk? Well I’ get to that later. Next is salt, that belongs to the ketchup list.
Now comes a key factor in duplicating this sauce from its rather formidable list of ingredients. Contains less than 2% of the following. Simply put we have already examined MORE than 98% of what makes up the sauce. The rest of the list boils down A-1 Steak Sauce, Tabasco Sauce, and Worcestershire Sauce.
Back to the egg yolk for a second. The egg yolk is used to bind the sauce together much like a custard or hollandaise sauce does. That's what I did. it was indistinguishable form the real stuff.
On the double boiler.
Jack In The Box Secret Sauce.
1 cup ketchup.
1/2 cup yellow mustard.
2 heaping Tbls dehydrated chopped onions re-hydrated in warm water and drained.
1/4 teas. A-1 Steak Sauce.
2 or 3 drops Tabasco Pepper Sauce.
1/8 teas Lea & Perrin’s Worcestershire Sauce.
1/2 cup water.
two egg yolks stirred to break up the yolks.
Combine all ingredients in the top of a double boiler and slowly heat over a medium flame stirring constantly. Stir until sauce thickens to the correct consistence–like a mayonnaise. Be careful to not allow the sauce to boil or the eggs will curdle.
