Bring a small pot of water to a boil. Note that the water needs to be deep enough so the egg(s) will be completely submerged when added. Once the water is boiling, lower the egg(s) into the water. Adjust the heat to maintain a low boil or strong simmer. Cook for 4 minutes for runny yolks and barely-set whites, 5 minutes for set whites and runny yolks, 6 minutes for partially set yolks, 7 minutes for soft-set yolks.
Lift the egg(s) out of the water. To serve in a cup, use a sharp knife or egg cutter to cut off the top of the shell so you can eat the egg out of the shell. To serve peeled, peel the egg(s) under cool running water.
Note: This method assumes you're starting with eggs cold from the refrigerator; if you're starting with room temperature eggs, shave a minute off the cook times.