In a pot, combine the onion peels with 1 liter of water and bring to a boil. Allow it to simmer for 25 minutes until the water darkens. Let the mixture cool, then add 2 tbsp of vinegar.
Boil the eggs to your desired consistency. You can refer to my other article on boiling eggs for guidance.
Transfer the onion water to a separate bowl or cups, ensuring no onion skins remain, and add the eggs. Let them soak for several hours or overnight for a more intense color.
Alternatively, leave the eggs in the onion water with the skins for a beautiful pattern. After soaking, carefully remove the stockings and decorations, then allow the eggs to dry naturally on a paper towel. Optionally, lightly coat the eggs with olive oil for a shiny finish.
Option 2 - Using Uncooked Eggs
Follow the same process as Option 1 to prepare the onion water.
Once cooled, add the eggs to the onion water or the mixture with onion skins for varied decoration patterns. Bring the water to a boil, then remove the pot from heat and let the eggs sit in the hot water for 3-6 minutes, depending on desired doneness.
Remove the eggs and allow them to dry on a paper towel. Optionally, you can leave the stockings and decorations on the eggs and return them to the pot with cooled down onion water for additional soaking. After drying, a light coating of olive oil can provide a glossy finish.