Prepared in 15 minutes or less plus 45 minutes to bake.
For the Leeks:
For the Egg Topping:
Preheat the oven to 400ºF.
Cut the leeks in half lengthwise and trim away all but 1⁄8- inch of the root, so that they hold together in one piece. Place in a bowl of cold water and loosen the dirt, then run cold water over them, fanning the layers to wash away excess dirt in between layers.
Lay the leeks side by side, cut side up, in a baking dish. They should fit snuglyin a single layer. Pour on the wine and sprinkle with the salt and pepper. Drizzle on the olive oil and place the lemon slices over the leeks. Top with the fresh parsley sprigs.
Tightly cover the baking dish tightly with foil and place in the oven. Roast for 30 minutes. Uncover, raise the heat to 450ºF, and return to the oven for another 15 minutes, until the leeks are tender but not mushy and are beginning to color very lightly. Remove from the heat and allow to cool.
Using tongs, carefully remove the leeks from the baking pan and arrange in a gratin dish or in a wide platter.
Pour the liquid in the pan into a bowl and whisk in the vinegar, lemon juice, salt, and olive oil. Pour over the leeks. Allow to cool, or if serving the next day, cover and chill.
For best results, refrigerate overnight. Bring back to room temperature before serving.
Chop the hard-boiled eggs very fine, and season with generously with salt and pepper. Arrange over the leeks, sprinkle with parsley, and serve. Serves 4.