Pre heat the oven to 180°C, Gas 4.
Line the loose bottomed tart case with1disc of pastry, leaving a good overlap.
Place the cherries into a saucepan and add a little of the strained juice, add the sugar and mix well.
Heat and then thicken with a little of the cornflour and water, once thickened, cool for 15 minutes.
Pour into the lined tart, moisten the edges with a little beaten egg. Top with the second disc, seal the edges well. Cut off any excess pastry and crimp decoratively.
Brush with beaten egg, and sprinkle with sugar, make 3 small incisions in the top of the pie and place in the oven.
Cook for 30-40 minutes until the top of the pie is golden.
Remove from the oven and cool before eating. Cut into wedges and serve with vanilla ice cream.