What does a cockney sandwhich mean?

"Cockney sandwich" isn't a recognized term in British slang or food culture. It's likely a made-up phrase or a misunderstanding.

It's possible someone is using "cockney" to describe a type of sandwich, but it's not a standard way to refer to any specific sandwich.

If you can provide more context or the full phrase, I might be able to figure out what it means.