Eggs are usually boiled for 5-10 minutes. You need to wash the eggs before boiling them, otherwise they will get dirty. Add water and cook until the water boils. Cook for another 5 minutes. The egg white is mostly cooked, but the yolk is not yet cooked. Cook for 7 minutes. The egg white is mature and the yolk is partially mature. This is what we often call sugar-soaked eggs; cook the egg whites and egg yolks for 10 minutes. Soak the hard-boiled eggs in cold water and remove. At this time, the taste is just right. If cooked for too long, the nutrients in the eggs will be destroyed and the taste will become stale.