The perfect boiled egg has a velvety yolk paired with a soft, solid white. Achieving this balance can be a challenge because the yolk cooks at a lower temperature than the white. Hard boiling an egg can yield a chalky yolk, while cooking low and slow can produce jelly-like, undercooked whites.

Boiling eggs just got a scientific upgrade. By alternating an egg between boiling and cool water, researchers have found a way to cook both the yolk and white optimally — leading to better texture and higher nutritional content than traditional methods.