Cut end from dark green leaves of leeks and slice in half lengthwise. Place in bowl of cold water for 10 minutes. Then rinse under faucet. Peel off outer layers and discard.

Heal olive oil in heavy skillet and place leeks in pan, cut side down. Cook, shaking pan and moving around with tongs, until lightly browned, about 3-4 minutes.

Using tongs, turn leeks over and cook on other side until lightly browned, 3-4 minutes. Season with salt and pepper.

Turn leeks back over so cut side is down. Peel off the outer layers, if they are papery, as they will not soften when the leeks are braised.

Pour in wine and stir to deglaze the bottom of pan. Add enough water or stock to come just to the top of the leeks.

Bring to a boil, reduce heat and simmer uncovered for 20-25 minutes, until leeks are thoroughly tender when pierced with a knife.

Most of the liquid should have evaporate. Meanwhile, preheat the broiler.

Transfer leeks to an oiled, ovenproof pan if your skillet cannot go under broiler. Using tongs, turn leeks so flat side is up. If there is still a lot of liquid in pan, pour it off.

Sprinkle Parmesan over leeks. Place under hot broiler until cheese has melted and begins to color. Remove from heat and serve. Can be made ahead and put under broiler before serving.