Combine the melted butter, watermelon jam, lemon juice and zest and salt and pepper.
Clean and rinse the prawns, then toss them in the marinade. Cover and chill for at least 30 minutes, or until ready to cook.
Braai the prawns on an open fire, for about 3 minutes a side, basting them with the extra marinade as you go. Serve warm or cool on the dressed salad.
To make the salad, slice the cucumber into ribbons using a vegetable peeler. Cut the apples into matchsticks and sprinkle with 2 T lemon juice to prevent them from going brown. Combine the remaining lemon juice, jam, olive oil and salt and pepper. Toss the cucumber, apple and salad leaves with the dressing.
To make the chilli-watermelon jam, finely dice the watermelon rind into 1 cm x 1 cm cubes. Chop the watermelon into 2 cm x 2 cm cubes and place in a saucepan with the watermelon rind over a medium heat. Add the rest of the ingredients and reduce the mixture by half until syrupy. Reduce the heat and cook gently for 30 to 45 minutes. To check if it’s ready place 1 t on a cold plate – you should be able to pull your finger through the mixture easily but it should hold its shape. If it doesn’t, reduce it further. It should be the consistency of golden syrup. Remove from the heat and allow to cool. Store extra jam in sterilised jars.