A poached egg is an egg that has been cooked in simmering water. It requires precise timing and is quite simple to master once you have the right technique. One method that is occasionally used by Chefs, consists of adding a little vinegar to the water, this helps maintain the egg white keeping the egg together. If too much is used, it may give the egg a slight acidic taste which is not favourable. Cooking times can vary depending whether the egg is straight from the fridge or the different egg sizes.