Onsen tamago

Onsen tamago (温泉卵 or 温泉玉子^?) is a traditional Japanese boiled egg which is originally slow cooked in the water of onsen hot springs in Japan.^[1]

The egg has a unique texture that the white tastes like a delicate custard (milky and soft) and the yolk comes out firm, but retains the color and creamy texture of an uncooked yolk.^[2] The special texture is cooked by using the difference between the temperature of which the egg yolk and egg white solidifies.^[3] The egg is poached within the shell and is served with the shell removed in a small cup with sauce of broth and soy sauce.