Place the egg or eggs in a small saucepan and cover with cold water by at least 2 cm. Place over medium-high heat and bring to a full boil. Once boiling, reduce the heat slightly to a gentle boil and cook for exactly 9–10 minutes for a fully set yolk that is still bright yellow and creamy in the center. While the egg cooks, prepare a bowl of ice-cold water (or very cold tap water). As soon as the timer is up, use a spoon to transfer the egg immediately into the cold water and leave it for at least 5 minutes. This stops the cooking instantly and makes peeling significantly easier. Once cooled, gently peel and then slice in half just before placing on the platter so the yolk stays bright and presentable.