Irish Potato Skins

Preheat oven to 400 degrees F.

Scrub each potato well, wrap each in a strip of aluminum foil about 6 inches wide and poke with a fork. Bake in preheated oven 50 minutes to an hour, or until potatoes are pierced easily with a thin knife. Unwrap potatoes and let them cool 20 minutes.

While potatoes bake, melt 1 tablespoon butter in medium skillet and saute chopped leeks until soft, about 10 minutes. Stir in vinegar. Set aside.

Cut potatoes into quarters lengthwise, then halve the quarters across the middle. Scoop away most of the potato flesh, leaving skins 1/4 inch thick.

Arrange potatoes skin-side down on two baking sheets. Add salt, pepper and thyme to the melted butter and brush mixture on potatoes. (Skins can be made a day ahead at this point, cooled, lightly covered and refrigerated. They'll have to come to room temperature before the final bake.)

Preheat oven to 425 degrees F.

Bake skins about 25 minutes, until crispy, rotating baking sheets midway. Carefully put about 1/2 teaspoon leek mixture over each skin, return sheets to oven and bake 3 more minutes. Let skins stand 5 minutes, then arrange on platters and garnish with a dollop of sour cream.