American fast-food giants like McDonald's, KFC, and Starbucks tweak their menus around the world to adjust to local tastes.

On a recent trip to South Korea, I made it my mission to eat as many fast-food menu items not available in the US as I could.

Standouts include KFC's Double Down, McDonald's bulgogi burger, and Taco Bell's squash soup.

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I like to consider myself a fast-food expert.

Having reported on chain restaurants for almost seven years, I have done a pretty good job eating my way from Applebee's to Zaxby's. But, my fast-food repertoire has been pretty focused on the US.

Most of my knowledge of menu items outside the US has come from social media. Years of browsing Twitter and Instagram helped convince me that fast-food chains are willing to be a bit more adventurous in menu creation in Asian countries. And, South Korea in particular has some gems.

On a recent trip to Seoul, I made it my mission to try as many fast-food menu items that I could not find in the US as possible. Here are 17 of the best and most bizarre things I ate at chains like KFC, McDonald's, and Taco Bell.