Method 
1. Combine the rice wine vinegar, palm sugar, lime leaves and chilli, in a small saucepan, place over a medium-low heat and simmer for 15-20 minutes. Pour into a bowl and place in the fridge to chill. Once chilled strain into a clean bowl and add the lime zest, juice and fish sauce.
2. Combine the watermelon, red onion, lime leaves and herbs in a bowl, using clean hands carefully mix. Set aside in the fridge.
3. Heat the vegetable oil in a wok until hot enough to deep fry. Combine the flour, garlic and onion powders, paprika and chilli powder in a bowl and season with salt and pepper. Prepare the calamari tubes by slitting the tubes along one side to open, flat and scoring in a criss-cross pattern, cut into 4 parts. Coat the calamari in the chilli powder, dust off excess and deep-fry in batches, for 30-60 seconds, careful not to over cook, drain onto a plate lined with paper towel.
4. Pour the dressing over the prepared salad and carefully mix.
5. Spoon the salad onto a serving plate and top with the calamari to serve.
