Place the egg in a large saucepan and add enough cold water to cover by 1 inch. Cover and quickly bring to a boil over high heat. Remove from heat and let stand for 15 minutes for large eggs (18 minutes for extra-large eggs and 12 minutes for medium). Drain the water and run cold water over the eggs until they are cool enough to handle. Peel and enjoy! The time you let the eggs sit in hot water is important. If you let them sit too long, they will become overcooked and rubbery. If you don’t let them sit long enough, they will be undercooked and runny.