Make the custard: in a large bowl, whisk the egg yolks, corn flour, vanilla and sugar together with 2 tbsp of the milk. Put the remaining milk in a non-stick pan and slowly bring to the boil.
When the milk is boiling, pour it onto the egg yolk mixture and stir well. Rinse out the saucepan, then pour the milk and egg mixture back in the pan. Cook gently for 6-8 minutes, until the mixture is thick enough to coat the back of a spoon; do not boil. Pour back into the bowl, cover the surface with nonstick baking paper to prevent a skin forming and leave to cool.
Split the trifle sponges, spread with the raspberry jam, then sandwich together. Cut each into two pieces and scatter over the base of a large glass dish. Scatter the fruit over the sponge., Mix the sherry and orange juice together and sprinkle over the fruit. Cover with the custard.
Whip the cream and icing sugar together until it forms soft peaks. Spoon on top of the custard. Scatter over the almonds. Serve chilled.
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