Did you know there's a technique for making perfect hard-boiled eggs?
Most people probably figure this is a cinch. Just cover the eggs with water and boil. Or, boil water and drop in the eggs.
For years I've been following my wife's method: cover eggs with cold water in a saucepan. Bring to a boil, then remove from the heat and let the eggs sit.
I wanted to teach this to the kids in my "food appreciation" classes. I figured six eggs in each class would be enough to make a deviled egg for everyone. So how much water to put in the pot and how long to sit?
My wife wasn't sure, so we went to the source: Julia Child's The Way to Cook. There, Child details an elaborate method for hard-boiling eggs that involves heating the eggs, then transferring them to an ice bath, then back into boiling water, then back into the ice bath. She also gives very specific amounts of water to use depending on the number of eggs. The length of time the eggs sit in the hot water after coming to a boil is always the same: 17 minutes.
That's much longer than what my wife told me. No wonder my yolks were always a bit soft.
Eggs are sold unfertilized and consist of three basic components: the yolk, or yellow part; the albumen, or white part, and the chalazae, which are cloudy strands like umbilical chords connecting the yolk to the white.
I had the kids separate eggs by hand just so they could feel the whites slither through their fingers and handle the yellow globes of yolk.
To demonstrate to the kids what happens when an egg cooks, I cracked one open into a skillet and fried it from the top with my kitchen torch. The kids marveled at how the proteins in the albumen seized up and turned from clear to white. In just a couple of minutes, the egg was cooked and they greedily ate it.
Meanwhile, I had a small pot of water with just a teaspoon of vinegar coming to a boil. I brought that to our demonstration table and cracked an egg into the water. The kids thought that was pretty gross. But soon enough, a poached egg emerged and they couldn't wait to dig into that as well.
All this time I'd had six eggs in 2 1/2 quarts of water (use a tall, rather than wide, pot--uncovered--for this) coming to a boil on the stove. As soon as it starts to boil, remove the pot, cover it and let the eggs sit for 17 minutes exactly. At the end of 17 minutes, transfer the eggs to a large bowl of iced water and put the pot back on the heat to return to a boil. Leave the eggs in the iced water for precisely 2 minutes. Remove them, and when the water on the stove comes back to a boil, plunge the eggs into the pot. Wait until the water again comes to a boil, count 10 seconds, then immediately remove the eggs, placing them back in the ice bath. They are now done.
Why all this back and forth? Chilling the eggs after cooking helps separate the albumen from the inside of the egg shell. Fresh eggs especially have a tendency to stick to the inside of the shell, which makes them difficult to peel. We've all experienced the hard-boiled egg that ended up a cratered mess because the shell just didn't want to come off.
If your yolks come out with a greenish-grey lining after you hard-boil them, you've cooked them too long. Egg whites contain a certain amount of sulfur that slowly decomposes into hydrogen sulfide (source of the famous rotten egg smell). Heating the egg greatly accelerates the decomposition process and the hydrogen sulfide migrates toward the yolk, where it combines with the iron in the yolk to make that dark ring. When eggs are cooked just long enough, the yolk comes out solid with no dark ring.
And why do your eggs crack when you boil them? First, eggs contain a small pocket of air that expands during cooking and can crack the egg. To let the air out, use a small trussing skewer or needle to make a hole at the blunt end of the egg. Plunge the skewer into the egg 1/4-inch. Secondly, cold eggs will crack if placed in hot water. Cover the eggs with cold water and bring them both up to heat: The chances of cracking are much less.
If somehow you should mix your hard-boiled eggs with your fresh eggs, how do you tell them apart? Try spinning them on your countertop. Fresh eggs will not spin. Hard-boiled eggs spin like a top.
Our hard-boiled eggs came out perfectly. The yolks were solid with no tell-tale ring. We sliced them in half lengthwise, then mashed the yolks with a teaspoon of Dijon mustard, about 1/4 cup mayonnaise and a generous pinch of salt. Then the kids took turns filling the eggs. Garnish with a sprinkle of paprika or chopped chives.
"Delicious!" the kids declared. And you know, they were.
Note: Julia Child says that to hard-boil 1 to 4 eggs, use 2 quarts of water; for 12 eggs, 3 1/2 quarts of water; for 24 eggs, 6 quarts of water. Do not attempt to cook more than 24 eggs at a time.