The term “boiled egg” is a misnomer, for eggs should always be gently simmered, not boiled, partly to avoid cracking the shells, partly so the whites do not become rubbery. The water should generously cover the eggs and, to gauge the cooking time correctly, the eggs are best lowered into water that is already simmering. However, they can also be put in cold water and brought to a boil, or put in boiling water and left to cook off the heat. The latter method, called coddling, produces a soft-cooked egg with a particularly tender white. To deter cracking, eggs should be at room temperature: a tablespoon or two of vinegar in the water will help seal leaks of white from any cracks. Some cooks also advocate piercing the eggshell with a pin.