Prepare the dipping sauce: In a bowl, mix all dipping sauce ingredients together. Adjust sweetness or acidity to taste and set aside.
Cook the prawns: Bring a pot of water to the boil. Add prawns and cook until they turn pink. Immediately transfer prawns to a bowl of cold water to stop the cooking process. Drain and set aside.
Cook the noodles: Boil a small pot of water and cook the rice stick noodles according to package instructions. Drain and set aside.
Prepare the rolling station: Fill a large bowl with warm water. Prepare a large flat plate for assembling the rice paper rolls.
Soften the rice paper: Dip one rice paper sheet into the warm water for a few seconds until just softened. Lay it flat on the plate.
Fill the rice paper: Place prawns, vegetables, and noodles in the lower center of the rice paper.
Roll: Fold the bottom edge over the filling, then fold the left and right sides inward like an envelope. Roll tightly to seal.
Serve: Repeat with remaining ingredients and serve immediately with the dipping sauce.