Heat the sesame oil in a wok until very hot but not smoking. Quickly fry the lemongrass and ginger for a minute. Throw in the carrot, red pepper, onion, chilli and spring onions. Stir-fry for just a minute or two and then add in the bean sprouts, soy sauce and chilli sauce. Stir-fry for another minute. Allow to cool. Next, take a rice wrapper and soak in a large dish with warm water for 10-15 seconds so it becomes pliable. Remove from the water and lay on a board. Use a piece of kitchen roll to remove any excess water. Place spoonfuls of the cooled vegetable filling in the middle of each wonton wrapper. Roll up tightly into spring rolls. Repeat the process with all the filling and wrappers. To serve, cut the vegetable spring rolls in half diagonally and place on a large plate with the plum or sweet chilli sauce on the side.