Reduce apple cider to one-eighth to one-tenth original volume, skimming off the foam and nasties. Whip in a couple cubes of cold butter at the end so it gets richer and glossier. Add a pinch of cayenne for heat. Seriously good, totally autumn. Had it with my smoked turkey and got raves all around. A bit sweet for some, could have thinned it with rice or cider vinegar or lemon juice, I suppose.