Slipper Lobster Tails In Leek Sauce

Wash leeks very well under cold, running water. Cut into bite-size strips, about 1/4" wide. Heat large skillet, add 4 Tbs butter, when melted add leeks and wine. Cover and cook on low heat for about 6 minutes, or until leeks are almost tender. Uncover and finish cooking and there is no liquid left in the skillet. Remove from heat and set aside. Reduce the lobster stock or clam juice by half, on high heat. Whisk in the Creme Fraiche and return the mixture to heat and reduce to about 1 cup--about 15 minutes, whisking constantly. Whisk in the reduced heavy cream and reduce the entire mixture until it is very thick. If the sauce isn't thick enough to your taste, add the Beurre Maine, 1 Tbs at a time until a satisfactory consistency is reached. Add the leeks to the sauce, but don't wash the skillet. Stir to combine well and set aside. Heat the skilled and when hot, add 4 Tbs butter. When melted add lobster tails. Mix frequently for about 5 or 6 minutes so the lobster is just about cooked. Don't overcook the lobster or it will be tough and horrible. Return the leek sauce to the skillet. Stir well and heat through over medium he