Boil water, sugar, ginger, lemongrass and kaffir leaves until sugar is dissolved. Stand 10 min, then pour through a fine sieve. Add lemon and lime juice, fish sauce and chili, stir well. Cool to room temperature.
Cut watermelon flesh into long slices, remove green rind from rind with a vegetable peeler, discard. Combine melon pieces and white rind in a baking bowl, add lemon zest and Thai basil, mix. Drizzle the dressing over the melons, stand min 10 min, but no more than 2 hours Just before serving, sprinkle with the chopped peanuts.
Secrets of Success : ~ Thai fish sauce balances the sweetness of the fruit and the tartness of the lemons very well. ~ Watermelon rind has an almost fennel-like texture and adds a crunchy accent.
Unusual, refreshing entrée. Very tasty.