This Thai/Vietnamese-influenced soup could be served as a starter or dessert; I love the combination of fruit and a bit of spice. Other melons would work just as well – or a selection – and if you can find seedless watermelons even better. Because of the size of watermelons you will have some left for breakfast.
1 small or half a large watermelon
3 sticks of lemon grass
10 kaffir lime leaves
30-40g root ginger
2 medium red chillies
2tbsp granulated sugar
A handful of Thai or normal basil leaves
Peel the watermelon, chop the rind into chunks and put it into a saucepan with the sugar, lime leaves and 1 litre of water, then gently bring to a simmer to make a stock syrup. Roughly chop two sticks of lemon grass and add them to the mixture; trim and finely chop the third stick and put to one side.
Peel the ginger and add the skin to the stock syrup, and roughly chop one of the chillies and add that too. Continue simmering the stock syrup for 20 minutes or until you have about 200-300ml left, then turn off the heat and leave to cool.
Meanwhile finely dice the ginger and chilli as small as you can and transfer it to a small saucepan with the retained lemongrass and about 200ml of the syrup, strained. Bring to the boil and simmer for 2-3 minutes and remove from the heat.
Strain the stock syrup through a fine-meshed sieve. Cut the melon into rough 2-3cm chunks and blend half of it with the stock syrup in a liquidiser until smooth. Mix the ginger, lemon grass and chilli mixture in the syrup with the blended melon. Place in a container in the freezer for about 45 minutes until it's ice cold and refrigerate the rest of the melon chunks.
To serve, arrange the chunks of melon in shallow soup/pasta bowls, pour the cold melon purée over so they are just showing and scatter the basil on top.