I found this recipe in "The Witness". It is so easy but unbelievably delicious. I changed the way you bake the pastry which makes it even easier!
1 Utra Mel Custard, 1 Vanilla Instant Pudding, 1 Box of Puff Pastry Sheets. ( I used Today puff pastry sheets. There are 4 sheets in the box.). 1 Beaten Egg. Icing sugar .
Place the pastry sheet on a board. Cut into equal size pieces. I cut into four strips downwards and then across the middle to get 8 pieces per sheet. Measure with a ruler to get even sized pieces. Place on a greased baking tray and brush with the beaten egg. Place a sheet of baking paper over the pastry and place another baking tray on top. This will allow the pastry to bake nice and crisp without rising. Bake at 200deg celcius for 20 minutes. (If the pastry is not brown enough put it back in the oven uncovered until it is nice and brown.). Depending on how much you want to fill the pastry with the custard you will need three or four sheets. I used three sheets as I like a lot of filling. So I had to bake 24 pieces of pastry and got 12 complete custard slices.
While the pastry is baking place the Ultra Mel in a bowl. Sprinkle the vanilla instant pudding over the custard and whisk vigorously until the mixture is smooth. Cover with clingwrap directly on the custard (so no skin forms) and refrigerate. The custard sets in 30 minutes.
When the pastry is cooled assemble the slices. Place one pastry slice on a board. Place as much custard on the pastry as you like. I piped mine on but had to use a spoon to do the last few as my piping bag broke! Place a second slice of pastry on top and drizzle with the icing sugar mixture. (mix icing sugar with a little water until thick and shiny).