cups (750 ml) water
cup (60 ml) kosher salt
The dried yellow skins of 3 onions
hard-cooked eggs, unpeeled
Combine the water, salt, and onion skins in a saucepan over moderate heat and bring to a boil. Simmer until the water turns brown, about 10 minutes. Let the water cool to room temperature. Crack the shells of the hard-cooked eggs but do not peel them. Place the eggs in a glass jar or bowl and pour the salt solution over them. Refrigerate covered for at least 24 hours, or up to 3 days before serving. To serve, peel and slice in half. Serves 4 to 6.