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Crunchyroll #93: Onsen Tamago from “Kakuriyo no Yadomeshi”

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Onsen tamago is a dish that’s a bit confusing when first translated. It means “hot spring egg,” which you’re probably thinking is a fancy name for a special kind of egg dish, but actually, it just means that it’s an egg cooked in a hot spring. Yes, you heard me right. Just as some Americans try to fry eggs on sidewalks (though admittedly for fun, no so much to eat), some onsens in Japan make eggs cooked in what is essentially bath water. Fun, right?

Well, admittedly, the temperature of those onsen tend to be around 160-170° F, which is way too hot for humans to sit in for any amount of time, so it’s not really bathwater, but seeing as onsen is normally synonomous for the pools of water meant for bathing, the connotation is a little startling. In Kakuriyo -Bed & Breakfast for Spirits-, Aoi is treated to an onsen tamago with some freshly bottled carbonated water by Odanna, the Ogre lord of Tenjin-ya.

If you’re not familiar, an onsen egg, while traditionally cooked in a hot spring, is also classified by its barely set white and gelled yolk. Unlike a soft-boiled egg, whose yolk is still runny, an onsen tamago has a moderately hardened yolk center with a peculiar jelly-like texture, and a silky soft white. This gelling process, which you normally don’t see in eggs, is caused by the low-slow heating method, which puts the yolk through a slower chemical change than cooking it at normal temperatures.

As someone who hates eggs but is weirdly obsessed with becoming a master of egg-cooking preparations, I knew that I had to try this out. The problem, however, was that I don’t own a hot spring, nor am I remotely close to one. But, my apartment complex DOES have a hot TUB, so I figured that was my next best option.

After some brief research pretty much told me it was impossible to cook eggs in a standard hot tub, I decided to ignore everything I read and take myself, my camera equipment, a strainer, and some eggs to chill by the pool on a sunny, but windy Wednesday afternoon. People on the internet with more experience than I had given me enough intel to gather that a typical onsen tamago needed to be left in a pool of water heated to roughly 158°F for about 45 minutes for a very softly cooked egg, up to an hour and a half for a firmer egg. So, I figured my hot tub, a cool 105°F, would be fine as long as I left it in for roughly two hours. Where did I get such confidence in my numbers? Looking back, I have no idea. I think I made them up.

I had a lot of questions. Would two hours be enough time? Would the egg taste like chlorine? Would it really be delicious enough to merit sitting around waiting for some eggs to cook? After an hour and 45 minutes I fished my eggs out of the pool and cracked them open. To this day, I am eternally grateful my management didn’t find the eggs in the hot tub, which I’m not sure they’d have been pleased about. But, the most important question, of course, is… did it work?

Click to watch the video below to see the full process, get the answers to my burning questions, and to see the results of this little science experiment.



Ingredients for Onsen Tamago


-Soy sauce and Dashi for seasoning, as desired


To Make the Onsen Tamago

1. Bring a pot of water up to 167°F, using a thermometer to monitor the temperature of the water. 

2. Add in eggs, and maintain temperature of water between 163-170°F for 13 minutes.

3. Remove eggs from water and let cool in an ice bath. Peel, and serve with a splash of soy sauce and dashi stock. Salt would work just as well, if you don’t have either of those things.


I hope you enjoyed this post! Check in next week for another recipe. To check out more anime food recipes, visit my blog. If you have any questions or comments, leave them below! I recently got a Twitter, so you can follow me at @yumpenguinsnack if you would like, and DEFINITELY feel free to send me food requests! My Tumblr is yumpenguinsnacks.tumblr.comFind me on Youtube for more video tutorials! Enjoy the food, and if you decide to recreate this dish, show me pics! 😀

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