MasterCook 9. Got the CD-ROM out of a discount bin some dozen years ago and still use it to this day. It still works perfectly fine, but between the documentation being
in a deprecated format and a UI designed for far smaller resolutions it's definitely feeling its age.
I've tried pretty much every non-subscription alternative I could find (for
years) but none of them really have the features I'm looking for; admittedly, I'm far fussier than most. One program came close, but the company went out of business so I couldn't buy a license.