Yep, as Barry pointed out, there is a recipe for it on their site.
Sorry, the only reason I didn't mention it was I thought the whole point was to have a quick ready made base substitute.
Instead of spending the time making the soup, you might as well make a proper base.
But if you do like soup, it's pretty tasty.
I also used half a carton of this, to which I added a good handful of lentils, cooked them up to make a sort of half dahl half base. Then made a pretty reasonable Dhansak with it.
Martin