Onsen Tamago Hot Spring Eggs at Yunomine Onsen

“I am making Onsen Tamago; I will see you back in the ryokan,” told Fafa before going down the stairs, leaving him at the bus stop beside the bridge leading to the river in the middle of Yunomine Onsen Village.

What I should have known better by then was giving the man only the headlines of my plans would never be enough.

“What is Onsen Tamago?” he followed me down the short steps. “You know, onsen egg — egg you make by boiling in the hot spring water!” I told him while lifting the bag with eggs I bought from the stall nearby earlier for the said purpose. I could see he was still confused, so I placed the net bag on the inner hook of the small wood and slowly lowered it so the eggs would be submersed in the boiling hot spring.

We reached Yunomine Onsen Village (the third-night stay during our Kumano Kodo Pilgrimage) an hour ago. After checking in and while looking for lunch, we passed by a group of teenagers (the same one I saw in the Tsubuyo Onsen later that day) having snacks beside the river, surrounded by a strong sulphuric smell emanating from the boiling water inside the miniature pond. I remember thinking that was such an odd place to hang out and eat.

Cooking Onsen Tamago in Yuzutsu

Later, in the hole-in-the-wall eatery where we had our lunch, I saw eggs with the sign “Onsen Tamago” sold in pieces or by dozens, along with other vegetables. That was when I put two and two together.

The miniature pond I saw earlier was Yuzutsu, a basin with hot spring water that can be used to cook eggs and other food types, including vegetables. So I got some from the place and ended up waiting beside nature’s hot pot basin for my eggs to get boiled.

“How long are you supposed to boil it for?” Fafa asked. “The guy said eleven minutes“, I answered, and with that, he decided to return to the ryokan, leaving me with my newly adopted experiment.

Minutes later, I returned to the ryokan with the freshly boiled bounties. We sat on the glass-covered verandah in our room, peeled the still-hot egg shell, seasoned with salt (also given by the restaurant owner/egg seller) and ate them.

The white part is so soft and reminded me of the top part of egg-tart. Meanwhile, the yolk part dominated the egg and was a wee bit runny, just the way I like it. It was the umami perfection version of a soft-boiled egg.

It might sound like an enormous exaggeration to say it was the best boiled egg I have ever had, but it could just be. So much so that I have been researching and trying to replicate it with the homemade version. So far, I have failed.

Could it be the mineral-rich hot spring water? Or the memory of standing in front of nature’s hot pot, bracing the sulphuric smell and sharing it with Fafa that made the Onsen Tamago taste divine? Hmm.. maybe I should stop trialing it at home and hope I’d be lucky enough to make another trip to Yunomine Onsen in this lifetime.

Ps. Yes, I know I am being too sappy towards a boiled egg!

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