Do not boil the egg, but simmer it. The egg should be at room temperature and the water should be gently simmering as you immerse the egg. Another precaution is to pierce the top of the rounded end with a needle before you put the egg in to simmer. To save an egg, should it crack, quickly add 1 or 2 tablespoons of vinegar to the cooking water. This should seal the shell and stop the white from leaking out.
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