Who Makes Double Stock?
Perhaps this is a silly question, but considering (a) the time and trouble required to make stock and reduce it; and (b) the affordability of decent prepared stocks, why not omit water from the equation and *use* stock to *make* stock?
I have read several places that this (and multiple iterations of this) was the common way in classical French cooking until the time of Escoffier--repeatedly moistening innumerable batches of meat to extract huge amounts of flavor. Obviously this is a waste of meat and an expensive one at that. But why not jumpstart the process by using storebought stock and then making your own double stock from it?
There is always frozen stock in the freezer and that's what I always use to poach chicken for salads, thus strengthening it. It's always on hand; sometimes I break off part of the stock and use it to deglaze pans, sometimes I want a really impressive soup or risotto and use it there. I do mark that bag of stock as DS, double strength (and sometimes it goes to triple). I may or may not begin with a litle canned broth; I never salt my own stock at all, so it's no biggie.
I enjoy making stocks, and have to disagree with the trouble part of your statement, and really the time statement, too. Great stocks are the difference in many dishes being blah and great. I use a turkey fryer pot (monstrously huge) and make veal stock and ultimately glaze, and a dark chicken and a light chicken stock, both of which I reduce to glaze form as well, and store in my deep freeze. They really don't take up much actual effort / time, just occasional skimming and attention when you reduce to a point of almost zero hydration.
If that doesn't do it for you, try saving some chicken carcasses (my butcher does this for me), and beef bones (also, butcher sells to me on the very cheap), and make a "one hour stock" in a pressure cooker. I do this in a pinch if I'm out of my glazes. It works amazingly well, and isn't all that expensive, especially considering the blah chemically taste you get from commercial stocks.
I am a bit of a bone broth or stock weirdo :) I do this ( double stock) when I am using my stock for chicken soup and want it *really* chicken-y. I don't use a boxed stock though, I use a homemade stock from the freezer and start a second stock with it along with fresh roasted bones in the crock pot for 24 hours.
If you are interested in different ideas and playing with broth- here is a cool video using beef feet. I did this for a week ( on a homemade Pho kick) -and the bone broth tastes really nice:
I do it sometimes, inspiration was mainly Heston B tv episodes.. Making strong chiken or duck stock with some veal, then reboiling and cooking stock with wings or tighs, sometime freezing and filtering for a stronger clear broth.. Works great. quite a lot of work. I did it also for fish stock - second time cooking crabs, very intense stuff, maybe too strong but very tasty..
You can do it that way. I'm with mamachef though. Make sure it is low or no sodium.
In fact there is a method on the web somewhere where people will take canned stock and add a few left over bones and some vegetables and "brighten it up" by cooking that. Then they recommend adding a little gelatin to the mix to simulate the mouth feel of genuine stock. I suspect the only way this would be worth it is with beef stock because it is so time consuming and expensive.