Hi Jason,
It has been a while since you posted this question so you may or may not read this. But I thought it might be worth mentioning a few of my tricks of how to imitate a sauce that you really like. This is kind of a hobby of mine, I love to try and make "secret sauces" at home. I am certainly no expert. There are certainly a lot of folks out there who are much better at this than I am, but they have not replied to your question yet. So I figured I would give it a shot.
The easiest way to begin is to look on the label of the bottle (bear with me, I know it doesn't tell you everything). Write down the ingredient list on a blank piece of paper and don't worry about "spices" because you may be able to figure that out. The first thing is to get the base right. They have to list the ingredients in the order of amount so that can give you a feel for how much of each thing you have in there. Now that you have listed out the ingredients, look at the nutritional information. In particular look at fat, calories, and sugar or carbohydrates. Then look at your list of ingredients and see which of those may be contributing those items. If your sauce lists soybean oil for example, you can get a feel for how much soybean oil you have given the fat and calories in the sauce. then you can estimate how much of other items you might have. You can even work out ratios of ingredients if you feel like doing the math.
This will hopefully get you to where you have a similar base to the sauce you are trying to copy, but it will still require some experimenting to get the ratios of base ingredients just right. Use all of your senses when you are putting it together (well maybe not hearing...).
To figure out some of the spices, try pouring a little bit of the sauce from the bottle out onto a white plate and spread it as thin as you can. Can you identify the spices that are in there? Often you can look and see which spices are included based on their color and shape, especially if you have played around with a lot of spices in the kitchen. If you need to, pick them out (i know it is tedious) with a toothpick so that you can inspect them more closely. You can also approximate the ratios of spices in this same way by getting a feel for how much volume of a specific spice you need to use in relationship to other spices and your liquid base. Try your own mix and put it on the plate next to the real thing. How do they differ? What are you missing? Taste is an obvious comparison and you should taste your sauce and theirs frequently back and forth to see how close you are getting. I am certain that it will take several trials and some of your attempts will be good, some will be bad. I suggest making very small trial samples to begin with (a couple of cups or less) until you start to get really close. This is a lot like detective work and any information you have might be helpful. Is there a special regional spice that the original cook would have thought would be the "perfect spice"? If the person who first made it was from Hawaii for example, there may be a unique spice (or maybe even pineapple juice) that they would add to their sauce to make it perfect. Things like this can help you deduce what might be in the sauce as well. Will you figure out the recipe for THE secret sauce? You might not, but you will likely be able to come up with something very close. And for most of us, really close is good enough especially if we or the folks that we are feeding can't tell the difference!
Hopefully this will be helpful for you in figuring out the recipe for yourself. It is a fun game to play and a pretty cheap hobby. the hard part is getting the kitchen all to yourself for that long!
Best of lluck!
-Matt
