Not sure what type of stove you're using, but I make sure to have a windscreen for mine (see OM's post about swirling winds!) and make allowance for lower boiling points at altitude; it's about 191F at 11K, so food does not re-hydrate as quickly . I add a few minutes on. My wife has issues with altitude acclimation, so we generally stay around a high trailhead for a day before going in and she takes aspirin to help things along.