Put sugar and water into a pan. Dissolve the sugar over a gentle heat. Then boil steadily until it forms a syrup, approx. 113C/235F. Beat the egg yolks well, then carefully pour the syrup on to them whisking all the time. Continue to whisk to a thick, mousse-like mixture.
Whip the cream. Fold the cream and vanilla essence into the mousse with the fruit and nuts. Pour into a 2 litre pudding bowl and freeze.