Place eggs in a bowl with warm water. Eggs are more likely to crack if they are placed in boiling water when they're cold.
Fill a small saucepan about 1/3 with water (or enough to cover the eggs). Add onion peel and bring to a boil. Boil for 5 to 10 minutes until onion peels release their color.
Remove eggs from warm water and place them in the pot, making sure they are fully submerged in water. Add more boiling water if needed. Boil 7 minutes, turning the eggs occasionally.
Remove eggs to a bowl of cold water. Once they are cooled, dry with paper towels and Tada!! You can also rub some oil on the shell to give them a nice shine.