To Make pastry - sift flour into a large bowl, add margarine. Rub into the flour until the mixture resembles breadcrumbs.
Add sugar, stir in water gradually until the mixture begins to stick together in large lumps
With one hand, collect the dough together to form a ball. Turn out onto a clean surface and gently knead into shape into an even ball.
Roll out and place in relevant baking trays. Chill for about 30 minutes. Pre-heat the oven to 200c/ 400f/ Gas 6
Neaten the edges of the pastry, line the pastry cases with greaseproof paper, and fill with baking beans. Blind bake in the pre-heated oven for about 15 minutes. Remove the beans and paper, and return to the oven to dry out for a further 5-10 minutes
Spread the base of the pastry cases with jam
Melt the margarine, sugar and syrup together in a pan, then add the cornflakes and mix. Spread this on top of the jam in the pastry case, and leave to cool and set.