GP said a restaurant, not a road-side 'caf'/'diner'. They'd be looking to be given something good, whatever the candidate wants/comes up with/thinks they can do well. e.g. a bad candidate returns literally just a fried egg on a plate, a good candidate returns a devilled egg neatly presented, say.

So it's just guessing what the interviewer wants?

As a restaurant customer, I would prefer a fried egg over a deviled one.

The restaurant owner is interviewing a chef, not a cook. Part of the chef's job will be to innovate -- new dishes for the menu, small changes to existing dishes when customers ask for it or particular ingredients aren't available, something completely different when a coeliac vegan turns up.

It's doing something technically impressive which a fellow domain expert can appreciate whether they'd personally order it from a menu or not.

Exactly. If the chef said "What kind of egg would you like?" the chef didn't get the job.

I guess that makes sense.

It's weird how different industries work - even if they're both creative ones. If a customer under-specifies what they want, and I just make what I think will wow them rather than what they were thinking of but didn't think to tell me, that's a bad job on my part for not engaging with them and finding out what they actually desired.

Not a customer though, an interviewer who asks you how you'd go about designing the architecture for an IoT-controlled fleet of egg-cracking robots.

You might talk in great detail about SoA design, and the interviewer might be hiring for a monolith, but still respect the acumen, you could still be a great fit.

It doesn't mean the chef's only going to be cooking tasting menus any more than it means the engineer has carte blanche over greenfield design or to rewrite an existing project.

Think if you’re good at cooking the answers become obvious. If you’re excellent at cooking even more so.