First of all, run a sharp knife down the back of the prawns and remove the little vein. This will make the prawns look nicer and taste better, as they will take on more flavour. Get a wok or pan very hot while you very finely slice your baby courgettes at an angle. Place these in a bowl and have all your ingredients ready to go, which is really important when you're stir-frying. To your hot pan, add the oil, prawns, lime zest and ginger. Stir-fry for around 2 minutes, until the prawns are lightly golden. Remove from the heat, and allow to cool for 30 seconds before adding your courgettes, lime juice, chilli and herbs. You can increase or decrease the quantity of chilli to your own taste. I prefer to use lots! Season with soy sauce and toss well, then serve on a plate. Eat straight away, while the courgettes are still nice and crunchy.