4 1/2 cups of caster sugar
1/2 cup of cocoa
1 1/2 cups milk
1 tsp vanilla essence
1/3 cup of good quality dark chocolate, roughly chopped
Place butter, sugar, cocoa and milk in a large deep pot (this is important, the fudge will boil up high!). Bring to the boil over a medium heat and cook until mixture reaches soft ball stage (116C). Stir occasionally whilst fudge is cooking with a wooden spoon.
Remove fudge from heat and beat with an electric mixer (beater) for about 3 minutes. Add the vanilla essence and chocolate, then beat for a further 4 minutes. The mixture should loose it's shine and go a little dull. Pour into a 33cm x 23cm baking tray, lined with baking paper and quickly smooth with plastic scraper. Score 3.5cm squares when cool and cut when cold.