4 1/2 lb (2 kg) watermelon
7/8 cup (200 g) granulated sugar
8 tbsp cornstarch (cornflour) dissolved in 8 tbsp water
4 tsp osmanthus flowers (or use candied rose or violet petals)           
1 oz (25 g) haw jelly, cubed 2 drops red flavouring colour (red food colouring)

1.  Halve and seed the watermelon and cut the pulp into small cubes. Set aside.

2.  Heat 4 1/2 cups (1 litre) water in a pot. Add the sugar and osmanthus flowers and bring to a boil, stirring, until the sugar dissolves. Skim off any foam. Add the red flavouring colour and cornstarch. Cook, stirring until the sauce becomes a thin glaze. Remove and let stand until cool. Place the watermelon and haw jelly cubes on a serving dish, cover with the sauce, and serve.