Pre-heat oven to 180°C/350°F/Gas Mark 4. Place the shortcrust pastry mix in a bowl fitted with whisk beaters, add 75ml water and mix on a slow speed until a dough is formed. DO NOT OVER MIX.
Roll or press into a shallow, greased tin 25cm x 35cm (10" x 14"). Use a fork on the base. Bake blind for 10-14 minutes.
Spread the jam onto the base.
Place the sponge mix in a bowl fitted with whisk beaters and blend in 225ml water with the almond essence on a slow speed for 1 minute. Scrape down and then mix on a medium speed for a further 4 minutes. Spread evenly over the jam and sprinkle with flak
Place in the oven and bakefor 20-25 minutes until sponge is golden brown.