You’ve made hard-boiled eggs for your salad, and then… surprise: a green circle surrounds the yolk. It’s common, but far from tasty. Despite the fact that you followed your instructions exactly, why does this minor inconvenience keep occurring? And, above importantly, how do you avoid it without becoming a Michelin-starred chef? Here are all of our tips for perfect hard-boiled eggs that taste as delicious as they look.

The culprit? An unexpected chemical reaction

That iconic greenish ring isn’t the result of a poor egg or a failed cooking attempt. It’s merely a reaction between the iron in the yolk and the sulfur in the white that results from overcooking. The end outcome is a little layer of iron sulfide, which is nontoxic but visually unattractive. Fortunately, a few changes are sufficient to eliminate this issue.

The surefire way for making flawless hard-boiled eggs

Begin chilly.

Place the eggs in a pot without crowding them. Cover the eggs with cold water, leaving about 3 to 5 cm of water over them.

Cook over medium heat. When the water begins to obviously boil, turn off the heat immediately.

Let time do its work.

Cover the pan and let the eggs soak in boiling water for 9 to 12 minutes, depending on size. For a slightly soft yolk, 9 minutes is enough. For a firm yolk, allow up to 12 minutes.

Express cooling

Meanwhile, prepare a bowl of iced water (or, failing that, very cold water). Plunge your eggs into it as soon as the resting time is over. This immediately stops the cooking process , prevents the green ring… and makes peeling easier!

Peel without stress

Once cooled (5 minutes is sufficient), peel the eggs under running cold water to easily remove the shell.