Dissolve the jelly in 500ml (2 cups)
boiling water. Pour into a shallow dish and refrigerate until set. Cut
into bite-sized cubes. Combine the custard powder and sugar, and
gradually stir in the milk until smooth. Stir over medium heat for 5
minutes, or until the mixture boils and thickens. Remove from the heat
and cover the surface with baking paper to prevent a skin forming. Put
the cake cubes in a 1 liter (4 cup) glass bowl and sprinkle them with
the sherry. Drain the peaches, reserving half the syrup. Brush the syrup
over the cake, then pour half the custard over the cake. Top with the
jelly, peaches and remaining custard. Smooth the whipped cream over the
top and sprinkle with almonds. Refrigerate overnight.