Egg yolk nutrition. Egg yolks are made up of about 15% protein and 27% fat, with the remainder mostly water and a small amount of essential minerals like phosphorus, selenium, zinc, and iron.

Cook the submerged egg for 40 seconds for a runny yolk and closer to a minute for a firm one. David Watsky/CNET Step 4 : Remove the egg gently from the water with a slotted spoon or wire skimmer.

Because you’re not adding extra oils or fats into the cooking process, boiled eggs are considered to be one of the healthiest ...