Very often when you boil eggs, the shells crack and the egg runs out. Furthermore, if eggs boil for too long, you will notice that they have a greenish ring round the yolk which is not very appealing.
To prevent that, always place the eggs in cold water. Add a tablespoonful of salt or vinegar and bring the water to a boil. Now turn off the fire and leave the eggs in the hot water with the pot covered for about 6 minutes for soft-boiled eggs and about 9 – 10 minutes for hard-boiled eggs. When you take the eggs out of the hot water, cool them under running cold water, or plunge them in a bowl with cold water.
Your boiled eggs will be perfect each time.