Pre-heat the oven to 200ºC. Spray a large baking tray with low calorie cooking spray and use it to grease thoroughly.
Make the cherry filling: Place a sieve over a measuring jug. Pour the defrosted cherries and juice into the sieve and allow the juice to drain into the jug. Place the drained cherries in a small saucepan.
Measure the amount of juice in the jug and if you have less than 150ml, you will need to make it up to 150ml with cold water. If you have more than 150ml of juice, drain some off and discard until you are left with 150ml of juice.
Pour the 150ml of juice (or juice and water mixture), into the saucepan with the cherries. Taste the cherries and their juice to find out how sweet they are. You need to decide if they need sweetening to suit your taste as cherries may vary in sweetness. We used 10g of white granulated sweetener to sweeten ours, but you may decide you need a little more or less. Add the sweetener to the cherries in the saucepan and stir in.
In a small bowl, mix the cornflour with 3 tsp water until smooth. Place the saucepan containing the sweetened cherries and juice over a medium heat. Stir in the cornflour mixture and simmer gently for 3-5 minutes, until thickened and glossy. Set aside and leave to cool.
To assemble the turnovers: Cut the wraps in half to make 8 semicircular pieces. Place a dessert spoonful of the cherry filling on one half of each semicircular wrap, leaving a wide gap around the edges.
Brush around the edge of each semicircular wrap with beaten egg. Fold the wrap over the filling to make a triangle with one curved edge.
Press the edges firmly with your fingertips to seal the turnovers. Crimp the edges by pressing down firmly with a fork. Repeat until you've made 8 turnovers, then place them on the large, greased baking tray. You may need to cook the turnovers in two batches depending on the size of your baking tray.
Brush the tops with beaten egg and sprinkle with a little white granulated sweetener.
Place in the oven for 8-10 minutes or until golden. Allow to cool slightly and serve warm, either alone or with a swirl of reduced fat aerosol cream. Take care as the filling will be very hot.