Greek Easter Eggs - cooking recipe

Ingredients

5 cups water
12 yellow onions, skins removed and reserved
2 tablespoons white vinegar
12 eggs
olive oil

Preparation

Combine water, onion skins, and vinegar in a pot; bring to a boil. Set aside onions for another use. Reduce heat, cover pot, and simmer, stirring occasionally to make sure skins are submerged, for 30 minutes. Remove pot from heat, remove cover, and cool dye to room temperature, at least 30 minutes.
Remove skins from dye and discard skins. Place eggs in the dye and bring to a boil; cook for 15 minutes. Remove pot from heat and leave eggs in the dye until a deep red color is reached, about 30 minutes more.
Transfer eggs to a wire rack to dry, about 15 minutes.
Rub olive oil onto each egg to make them shiny. Store eggs in the refrigerator.