Recipe courtesy of Bungalow (now closed)

Seemingly simple on the surface, cooking just eggs (not even onsen eggs) is actually a skill that not that many people have mastered. There was once even an episode of MasterChef where contestants had to make a three-egg omelette, a sunny-side-up egg, a poached egg and a soft-boiled egg (season 3, episode 12, in case you’re wondering).

Now, there’s a lot of information out there on how to make the perfect soft-, medium- and hard-boiled eggs, so instead, we’re going to tell you how to make the quintessential onsen egg.

The perfect onsen egg is what dreams are made of, showcasing a barely cooked white and a gooey yolk that oozes out when you break it open. Onsen eggs can be tricky to make, but there’s a nifty method of doing it right every time.

And if you’re not convinced that cooking is a true science, the reasoning behind this recipe will convert you (for those non-science geeks who just want to make an onsen egg, please feel free to skip ahead).


A perfect onsen egg on top of a ricebowl
Photo by Cera on Unsplash

The two tricks to the perfect onsen egg

The first trick is to use 90°C water in order to simulate the conditions of a hot spring (which is how traditional onsen eggs are made in Japan). Yes, traditional hot springs are more like 60°C, but hot springs have a consistent temperature, which is harder to simulate at home so we up the temperature.

The second trick is to use a thermos because it causes the water temperature to fall at a consistent 2°C per minute. This has the same effect on an egg as a consistent 60°C hot-spring temperature. When you wrap the egg in kitchen roll, it protects the egg from the initial high heat. Also, if you forget about the egg in the thermos, it’s okay because the temperature will eventually drop to a degree where the water is no longer hot enough to cook the egg, and it shall forever (or until you eat it, which won’t be long) remain a perfectly cooked onsen egg.


How to cook an onsen egg

  1. Boil water to 90°C (that’s when small bubbles have formed on the surface but before it’s completely boiling).
  2. Wrap an egg in kitchen roll (it doesn’t matter if the egg is at room temperature or straight from the fridge).
  3. Put the wrapped egg in a thermos and pour the boiling water over it so that the water completely covers the egg (see step 1).
  4. Wait 15–20 minutes (some testing will need to be done as the cooking time depends on the size of the egg and the thermos’ heat-retaining ability).
  5. Take the egg out, crack open into a bowl and enjoy!

RELATED: Salmon and egg rice – in the rice cooker!


For more recipes like this, like Foodie on Facebook

Creating and delivering memorable experiences in both nightlife and dining.

Win tasty prizes in our Valentine’s Day giveaway!

Join our biggest giveaway yet and win prizes for you and your partner