Not sure if it is still in production, but it definitely has jogger knobs for power and time, and both can be modified while it operates. I’ve bought two (I gave first one to my parents because I loved the usability). Only flaw that I have noticed is that the writing wears off the start and stop buttons.
For the record I recently replaced one of them (mechanical timer) on an industrial grade dryng machine because a spring broke inside its clockwork, the machine (and the original timer) were manufactured 1978.
But, it could be a couple +/- buttons with TIME written on it and another couple buttons +/- with POWER, but then you would need a display, and then you would need backlight to it (people are reknown to cook in the dark), and then you would add a +10/-10 seconds button for daster setting the time, and possibly 4 or 5 "presets" buttons, each with a totally not understandable icon (is that a french baguette? But the setting is to just heat it a bit or to defrost it? and is that a pigeon, a chicken or a turkey?, etc.) or written in teeny-tiny fonts that the average user won't be able to read without spectacles ...
Compare this:
https://www.123rf.com/photo_33509347_close-up-of-modern-micr...
with - say - this:
https://www.123rf.com/photo_11190552_control-panel-wtite-mic...
You could easily reduce the complexity of the actual controls, but it would still be a digital microwave.