We bought a jar of aji paste a while back at Northgate Market to use for making anticuchos. Since we only used a little bit of the paste (it is very concentrated stuff), we wanted to come up with some other uses for it.
Turns out that it makes a very nice marinade for hanger steak. We used the same marinade we used for the anticuchos.
We cooked it up on the barbecue, keeping it nice and rare (which is important with hanger steak -- it doesn't do well if you cook it too hard). It was fantastic -- the aji complemented the slightly gamey flavor the of the meat really well.
Since we've made hot sauce from our red chiles a bunch of times, we decided to experiment with a yellow hot sauce using the aji paste as the base. Instead of mellowing it with roasted red pepper, we roasted some yellow peppers instead. The result was interesting, but more mild than we would have liked. We plan to try again -- maybe omitting the yellow peppers.