A questioner said:

Found this left in the kitchen of a newly-bought house, it’s about the size of a standard home oven rack. We’ve been stumped for years. Much of the house hadn’t been updated since the early sixties and the kitchen in particular was a near-time capsule – seems likely this hails from that era, but we can’t know for sure. Any ideas?

More from the owner:

Additional details are in the sub header. I posted this to some culinary groups about three years back, but no one could identify it for sure. I’m fairly certain it’s a cooking implement, though, given that it was found in the kitchen.

Some of the people opinions on it:

This sub has taught me more about random kitchen gadgets that I would have ever imagined was possible.
It’s a Barbecue Appetizer Pan
You could probably use it as a takoyaki pan
You kept it for years? Hoping one day you would find out how to use it? are you going to try it now?
And here’s me, thinking it looks like something you could poach a dozen eggs in simultaneously
I’d still say that would make some banging Yorkshire puddings.