Salt (to taste) In a medium saucepan place the 1 tablespoon of butter and heat it on medium high until it has melted. Add the shallots and garlic. Saut� them for 2 to 3 minutes, or until the shallots are tender. Add the Chablis, clam juice, and white wine vinegar. Cook the ingredients for 15 to 20 minutes, or until it is reduced to quarter cup. Add the heavy cream and the lemon juice. Reduce the heat to low and simmer the ingredients for 1 to 2 minutes, or until the liquid starts to thicken. Raise the heat to medium. While whisking constantly, add the pieces of butter one at a time. Strain the sauce into a blender. Add the basil leaves. Pur�e the sauce and then season it with the salt. Add some water if the sauce is too thick.