Whisky and Walnut Toffee

• 6 oz / 170 g walnut halves
• 1 lb / 455

Place the walnuts in a buttered or oiled cake tin or Swiss roll tin. Place the sugar and water in a heavy saucepan. Melt the sugar over low heat, then bring to the boil, and boil for 20 minutes. Add the butter and whisky and continue boiling until a piece becomes brittle when dropped into cold water. Pour immediately over the walnuts. When the toffee is almost set, mark into squares so that it