A sandwich by another name...

I don't know about this, but one thing I did think of is alternate popular ready-made sandwiches, avocado and bacon is one of the best sandwiches ever (I know this makes me a heretic but it's better than the BLT by a small margin) but I've never seen them as a commercial thing.
 
I think it might be known as Stacks.

That's not a bad name but more likely as developing from a stacked i.e. double
/sandwich/.

It's a bit like here where the "doorstop" came from the "doorstop sandwich" - so-called as the bread and filling are really thick making it a giant sandwich and akin to a door stop.

Hmm brickerbread or slatebread? as in bread stuck together like bricks or slate?
 
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