Preheat the oven at 347°F.
Roll the pastry out and sprinkle the caster sugar and coloured sugar decorations all over the surface.
Press lightly with a rolling pin, then cut into rectangles.
Bake for 10 minutes or until lightly golden brown.
Let them cool and place some pineapple cubes on each puff pastry layer.
Dust with icing sugar and store in fridge for few days.