Hot Spring Eggs (Onsen Tamago)

I've migrated to New Zealand. There's a hot spring in my backyard . . .

Just kidding. I'm still in Singapore, where there're all of two hot springs in the country.

Do I go to Sembawang or Tekong to make hot spring eggs?
Hell no.

Hot spring eggs are made by steeping eggs in hot water.

If the water is in a hot spring, that's nice. If it isn't, I'd know but the eggs wouldn't.

If you have an easy way to keep water at 64ºC, making hot spring eggs is easy.

I use a rice cooker that has an extended keep warm function.

Some rice cookers and multi cookers have temperature control. You could also use a sous vide machine.

What if you don't have an appliance that keeps water at a constant temperature?

You could monitor the water with a thermometer. Add some boiling water whenever the temperature dips. This is workable if you don't mind staying by the pot whilst the eggs cook.

What if you don't have a thermometer? Can you mix boiling and cold water in a pot, put your eggs in the water, set your timer, and walk away?


This method is a bit hit-or-miss. How cold is your cold water? How many eggs are you cooking? How well does your pot retain heat? All these factors affect the temperature of the cooking water. If you don't know what the temperature is, you're just stabbing in the dark.

What are the rewards for making onsen tamago successfully?

I love how the egg falls out of the shell, in one piece. One moment it's in the shell. The next moment it's sitting in the bowl, looking so pretty.

After cooking onsen tamago, I always take a few moments to marvel at how soft and smooth the egg white is. When I break the yolk, there's a beautiful contrast of colours. I almost can't bear to eat the egg that's a feast for the eyes. But eat it I must for the smooth and creamy egg is also a feast for the mouth. Unfortunately, it's a very small feast.

ONSEN TAMAGO (HOT SPRING EGGS) (Recipe for 1 egg) 1 egg, 65-70 g, cold 64ºC water 1 tsp soba sauce dilute with 2 tsp hot water spring onions to taste, sliced Cook egg in 64ºC water, totally submerged, for 1 hour. Crack into soba sauce. Sprinkle with spring onions. Serve immediately. 🌹 The easiest way to cook eggs in 64ºC water: use a rice cooker, multi cooker or sous vide cooker that may be set at 64ºC. I use the extended keep warm function of my rice cooker.

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