It's a pretty simple trick. Take your peeled, boiled egg and place it on your cutting board. Place your chef's knife towards the bolster on the egg, and gently pull the knife back. The egg will roll along the knife, cutting it through the white while leaving the yolk intact.
Make sure your water is hot.
There is well-researched advice that suggests a hot start (adding eggs to hot water) makes for easier-peeling than a cold start (covering eggs with cold water and putting the pot onto boil).
An egg slicer is a food preparation utensil used to slice peeled, hard-boiled eggs quickly and evenly. An egg slicer consists of a slotted dish for holding the egg and a hinged plate of wires or blades that can be closed to slice.
Why are fresh eggs so hard to peel? The fresher the eggs, the harder they are to peel. This is because the egg white or “albumen” in a fresh egg has a relatively low pH level, making it acidic. When cooked, these fresh egg whites bond strongly to the inner shell's membrane.
Shocking your recently boiled eggs by submerging them into a bowl of ice water is key. The quick cooling of the hard-boiled eggs causes the egg whites to contract, freeing them from the membrane. If you let them cool for about 15 minutes, the peeling is much easier.
Hard-cooked eggs may be difficult to peel if they are very fresh. This is because an egg shrinks inside during storage, which pulls the inner membrane away from the inside of the shell. For this reason, a hard-cooked egg will peel more easily if it has been stored for 1 or 2 weeks before it is cooked.
Some people prefer to peel their hard-boiled eggs before storing – and that's A-OK. You'll just need to take a few extra steps: Transfer hard-boiled eggs to a bowl of cold water immediately after cooking to help them cool down faster. Peel the eggs under running water.
If you have a bread knife with a serrated edge, use this as it is perfect for slicing tomatoes, ripe fruit and hard-boiled eggs. If not, make sure your knife is sharp and draw the blade across the surface of the egg without too much pressure.
Once cooled, gently tap the egg against a hard surface to break the shell all around it. Roll the egg gently between the palms of your hands to loosen the shell even more. Peel the eggs under cold water, starting on the larger end, until it's completely peeled.
Slicing hard-cooked eggs into wedges can be a bit messy and often results in crumbled yolks. It is, however, done easily and neatly using a long piece of unflavored dental floss. Simply pull the floss taut, then slide it lengthwise through the egg, cutting it in half.
At the lower pH of a fresh egg, the proteins in the egg white bind tightly to the keratin in the membrane during the cooking process, which makes it nearly impossible to remove the shell without chunks of white attached.
Boil for 6 – 7 minutes over medium-high heat for perfect hard-boiled eggs. Using a slotted spoon, transfer them to a large bowl of ice water and let them cool for a few minutes. Or you can place them under cool running water to stop the cooking.
As soon as the water begins to boil, turn off the heat and cover the pot. Leave the eggs in the hot water for anywhere from 10-12 minutes, depending on how you like your eggs. The 10-minute eggs will have vibrant, creamy yolks, while the 12-minute yolks will be paler and opaque, with a chalkier texture.
Once the water is at a rolling boil, turn off the heat and cover the pot with the lid. Allow the eggs to sit in the hot water for the following times according to the desired doneness: 3 minutes for SOFT boiled; 6 minutes for MEDIUM boiled; 12 minutes for HARD boiled.
With a butter knife, hit the side of your egg with a quick, decisive whack. This should cut through the shell and most of the egg. Then simply lift the knife, thus lifting the top of the egg, and remove.
When you hard cook an egg, this air heats up, expands, and escapes through pores in the shell—but not before the egg white sets. This leaves the egg with a flattened end. Pricking the egg provides a quick escape route for the air, which gives you an egg with a smoothly rounded end.
Give the eggs at least five minutes in the ice bath before you try to peel them—letting them cool may help make it easier to peel them, but it's also so you don't burn your hands.
When you plunge the eggs into a bowl of ice and water, the shock of the cold water stops the cooking process, preventing them from overcooking, explains The Spruce Eats. Otherwise, the residual heat in the eggs will continue to cook them, even after they have been removed from the source of heat.