Preheat a grill to high or light a charcoal barbecue.
Mix garlic, chilli, ginger, dill, sugar, lemon juice, and 60ml water with fish sauce.
Score the fish skin three times on both sides.
Marinate the fish with the mixture and lemongrass for 20 minutes.
Grill the fish for 10 minutes per side until thoroughly cooked and cool.
Combine crushed pineapple, fish sauce, lemon juice, chilli, and 60ml water for the sauce.
Moisten a rice paper sheet with cold water until pliable.
Place cooked noodles and a tablespoon of de-boned fish onto the paper.
Add carrot, cucumber, courgette, pineapple, and dill sprigs.
Fold the sides in and roll the rice paper tightly around the filling.
Repeat for remaining rolls and serve with the pineapple dipping sauce.