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Super Simple Onsen Tamago Recipe – 温泉卵

Welcome to the first recipe ever on The Chef Dojo! You only need two ingredients — eggs, and water.

I tried to choose the simplest dish possible — onsen tamago(温泉卵), which literally translates to “hot spring egg”. Here’s a beautiful picture I found of what it should look like:

Onsen Tamago

This onsen tamago recipe will be broken down into three parts — equipment / ingredients needed, short instructions, detailed step-by-step instructions, and any additional notes or thoughts I have.

Let’s get started!

Onsen Tamago Recipe(温泉卵)


  • a pot with lid
  • a spoon / ladle



  • 3 or 4 eggs
  • 1.2 L of water


Quick version

Bring 1 L of water to boil in a pot. Take pot off heat. Pour in 200mL of cold water. Put eggs in pot, and cover with lid. Wait 12-15 minutes. Rinse under cold water. Eat!

Detailed version

This onsen tamago recipe is adapted from the awesome Cooking with Chef Dai channel on Youtube. It is more or less the same except I used slightly less water.

Step 1

Bring 1 litre of water to boil in a small pot (the water should be enough to completely cover the eggs). Leave your eggs in the fridge until Step 3. It is better to cook them from cold.

onsen tamago recipe step 1

Step 2

Once the water is bubbling, turn off the heat and immediate pour 200 mL of cold water into it.

onsen tamago recipe step 2

If you are using an electric stove, you will need to take the entire pot off the stove and put it on a cutting board / towel / heat-safe coaster thing as the residual heat from the stove will continue to boil the water.

Step 3

Take your eggs out from the fridge, and VERY GENTLY, place them one by one into the pot. Use a big spoon/ladle, or a pair of tongs. Once the eggs are all in the water, immediately cover the pot with a lid so that no air can escape.

onsen tamago recipe step 3

Step 4

Sit back and wait. It usually takes about 12-15 minutes, depending on the thickness of your pot and size of eggs.

onsen tamago recipe step 4

Chef Dai recommends 10 minutes for small eggs, 12 minutes for medium eggs, and 15 minutes for large eggs. But, what exactly is considered a small egg? I figure everyone’s egg sizes differ slightly.

If you want to be extra careful, just do 15 minutes. If they are overcooked/undercooked to your liking, adjust for next time.

Step 5

After 12-15 minutes, take off the lid and place the pot under running cold water until the eggs are cool. Probably a minute or two is enough. You could also put the eggs into a bowl of ice water. You’re done!

onsen tamago recipe step 5

Step 6

Crack open an egg, eat directly or serve over a bowl of hot rice. The eggs should be soft, gooey, creamy and f*cking delicious. Put a dash of soy sauce and some chopped spring onions on top to make it extra fancy.

onsen tamago recipe step 6

Potentially, your onsen tamago could look as beautiful as this:

onsen tamago recipe finished

Notes and other thoughts:

  • Onsen Tamago is traditionally cooked in an actual natural onsen (i.e. hot spring). Hence the name.
  • The special texture of the egg is achieved because the egg white and egg yolk solidify at different temperatures. The egg yolk solidifies around 70 degrees Celicius (158 F), while the egg white doesn’t completely solidify until a higher temperature (80 C / 176 F). By keeping the water at or just below 70 degrees, you can get a creamy cooked yolk, with slightly runny egg white. Some onsens around Japan naturally maintain the perfect temperature for cooking onsen tamago. I lived a winter at one of the more famous places – Nozawa Onsen. It was awesome!
  • This onsen tamago recipe is not the most precise way of cooking, but if you are a perfectionist, you could constantly measure the temperature of the water with a thermometer.
  • If you want to cook more or less eggs at a time, just adjust the volume of water but keep the same ratio. This recipe cooks about 4 eggs, so if you want to do 8, just double the water: 2000 mL boiling water and 400 mL of cold water. Ratio of 5:1.
  • A traditional sauce is made by combining dashi, mirin, and soy sauce.
  • If you have no stove, you can try cooking onsen tamago in a microwave. Check it out here.


That’s it. Just two ingredients. Making onsen tamago is cheap, and simple as pie. Simpler. And, just as delicious. Serve over plain white rice, or any rice bowl (i.e. donburi) for a perfect combination.

I usually cook three or four eggs at once, and eat them over a couple of days. You can store the eggs in the fridge for 2-3 days.

What do you think of onsen tamago? Let me know in the comments!

Chef Goku

Chef Goku

Chef Goku is the founder and sole operator of The Chef Dojo. He loves Japanese food, and has lived in and out of Japan for many years. He started this blog in 2018 to share everything he learns about Japanese food and cooking. He is also a self-certified Japanese knife nerd. Contact Chef Goku

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