But is Irish guacamole just Peruvian guacamole served in Ireland?

As a major guacamole and mashed potato fan the answer is no. Too many major differences. Potato is a vegetable and avocado is a fruit. Mashed potato is primarily potato with spices and an oil while guac is a fruit with a few other fruits, fruit juices, vegetables like onion, and some spices. Guac also functions primarily as a dip while mashed potato is stand alone with the ability to function as a dip. They aren't similar enough to be analogous.

Guys is this mashed thing this other thing because it's mashed too?

They will not take away my mash n toast

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Potatoes are food for famine not thought.

I feel like reading this is like a thought crime.

This seems like as good a place as any to assert a much more defensible position: frito pie is Texan poutine.

This would be true if a potato was a fruit.