Fill a saucepan about two-thirds full with water and bring it to a gentle boil.
Use a spoon or some other handy tool to lower the egg into the gently boiling water. Adjust the heat so the water barely bubbles, then cook for 3 to 5 minutes, the lower time if you want the yolk completely runny and the white still slightly liquid, the higher if you want the white very soft but set.
Run the egg briefly under cold water, crack the shell, and scoop out the egg. Sprinkle with salt and pepper if you like and serve.