I have to admit that it took me years to figure out how to hard boil an egg. I could never remember what made them hard vs. easy to peel: whether it was over cooking or under cooking, or if it was using older eggs or newer ones. I never knew how long to boil them, so I just let them go. Sometimes until the pan boiled completely dry (a method that I don’t recommend). A few years ago I happened to catch a segment on a cooking show about hard boiling eggs. I thought, “Really? This is something that needs to be explained?!” As it turns out, it was. The tip was how to get hard boiled eggs that have a perfectly yellow yolk without that gray-green ring around it. I had never given it any thought before, but quickly realized that my eggs always looked like this:
Start by heating a pan of water until boiling. While the water is heating, take a safety pin or needle and carefully poke a hole in the larger end of the egg. I assume this is the bottom, but I’m not good with things like that, since I can’t stand them up: my eggs lie on their sides if I’m lucky, and roll off the counter if I’m not. But if you look closely, you’ll see that one end of the egg is wider, and that’s the end to poke. There’s a little gap (a millimeter or two) between the shell and the membrane on that end, so don’t poke too deep or you’ll pierce the membrane and have egg white leaking out.
Poking this hole will allow the pressure to be released from the egg when it hits the boiling water. Without this hole, the pressure can build up and crack the egg shell. Gently lower each pierced egg into the boiling water, and set the timer for 15 minutes.
You can lower the heat to a more gentle boil, but I don’t find that’s really necessary unless your water is boiling over. As for the 15 minutes, that seems to be the best time frame for fully cooking any egg, including extra large eggs that are still cold from the refrigerator. Feel free to experiment with shorter cooking times (say, 10-12 minutes) for smaller eggs.
While the eggs are boiling, prepare a bowl of cold water and ice cubes. There is no exact measurement to follow, but the bowl should be about the size of the pan, so you know the eggs will fit. Add enough ice that the hot eggs won’t melt it right away. When the timer goes off, remove each egg from the boiling water and drop it into the ice water.
Now here’s the secret trick to avoiding the ring: smash the eggs a little bit against the side of the bowl. That’s right, break the shells a little, then submerge them in the ice water.
From what I remember, these crushed holes will allow the sulfur inside to escape into the ice water, and that this gas is what would otherwise cause the ring. I don’t remember the science behind it; I just know it works.
After about 15 minutes in the water, take them out and either peel ‘n eat them right away or store them in the refrigerator (put them in a plastic bag, so the exposed egg white on the smashed side doesn’t dry out and get rubbery).
Enjoy your ring-free hard boiled eggs!
P.S. To make the eggs easier to peel, peel them under running water.