Not sure why you want to breakfast in a lounge when you are flying Business. You may not get cooked breakfast but can expect half-decent food on the plane.

The lounge to use would be the Bellevue Lounge in Terminal E but it didn't use to be very convenient for US-bound flights. Not sure if it's still the case.

Whether LX16 has the new Business Class seems to vary from day to day according to the more recent posts in this thread.