To prepare the white chocolate and ginger nut truffles, you will need: White chocolate: Melt the chocolate in a double boiler over low heat, stirring constantly, until it is completely melted and smooth. Add the sugar and stir until dissolved. Stir in the vanilla extract and beat the mixture with an electric mixer on medium-high speed until smooth and fluffy, about 5 minutes. Remove the bowl from the heat and add the egg yolks and vanilla. Beat the ingredients together until they are well-combined. Pour the batter into the prepared baking dish and bake for 18 to 20 minutes or until the center is set and the top is golden brown. Allow to cool before cutting into squares.