To freeze the rosé and watermelon
The day before, pour the rosé into a wide stainless steel bowl, line a container with baking paper, place the melon on top, freeze both for at least 8 hrs. or overnight.
Strawberry and mint syrup
Bring the water and sugar to the boil in a pan, simmer until the sugar has dissolved. Remove the pan from the heat, add the mint and strawberries, stir well, leave to cool in the liquid, strain the strawberries and mint, retain the syrup.
Transfer the frozen rosé to a large blending cup along with the watermelon and syrup, blend until smooth. Pour the frosé into glasses and garnish with strawberries and mint.