Dark Chocolate Fudge

2 Tbsp. butter or margarine 3 1/2 cups sugar 1/2 teaspoon salt 1 1/2 cups walnuts or pecans 4 ounces unsweetened chocolate

8 ounces bittersweet or semisweet chocolate 1 1/2 cups half and half 1/4 cup light corn syrup 2 tsp. Vanilla

Smoothly line an 8 or 9 inch square pan with foil. Lightly butter foil. In a 3 to 4 qt pan, mix half and half, sugar, corn syrup and salt. Stir occasionally over high heat until simmering, about 3 minutes. With a brush dipped in water, frequently wipe off beads of syrup that form on the sides of the pan. Reduce heat to medium. Add bittersweet and unsweetened chocolate; gently stir until chocolate melts and mixture begins to simmer, 3 to 6 minutes. Insert a candy thermometer into mixture. Boil, occasionally stirring and washing sides of pan with wet brush, until mixture reaches 235 degrees (or a drop of candy spooned into cold water forms a soft ball that flattens when removed from water), 30 to 40 minutes longer. Immediately pour fudge mixture into a 10 by 15 inch rimmed pan. Dot with 2 tablespoons butter and vanilla. Let stand undisturbed until a thermometer inserted in center of candy registers 115 degrees (pan is warm to touch), 20 to 30 minutes. With a wide metal spatula, scrape mixture back and forth in pan until it becomes smooth and glossy and starts to thicken and mound but is still soft and malleable, 4 to 10 minutes. Add nuts and mix just enough to distribute. Scrape fudge into foil-lined pan. Let stand until firm to touch, at least 2 hours. Invert pan to release candy. Peel off foil. With a sharp knife, cut fudge into 1 inch squares and serve. Or wrap the uncut fudge airtight and store at room temperature up to 1 week.