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 1/4 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.