Pour 1 L of water into the saucepan and dissolve the chicken stock cube over medium heat.

Add the grated carrot and grated courgette, then simmer until slightly softened.

Season the vegetables with 1/4 tsp salt, 1/4 tsp black pepper, and 1 tsp soy sauce.

Soak the rice vermicelli in boiling water until tender, then drain it thoroughly.

Cut the drained vermicelli into short lengths and stir it into the vegetable mixture.

Let the vegetable and vermicelli mixture cool completely, then transfer it to the mixing bowl.

Add the minced chicken breast and chopped onion to the cooled mixture.

Add the egg, remaining soy sauce, salt, and black pepper, then mix until evenly combined.

Soak one rice paper wrapper in warm water until pliable, then place it on the clean kitchen towel.

Place about 2 tbsp of filling near the lower edge of the wrapper and fold in both sides.

Roll the wrapper tightly into a cylinder and repeat with the remaining wrappers and filling.

Heat the vegetable oil in the frying pan and fry the rolls on both sides until golden brown.

Transfer the fried rolls to a serving plate and serve hot.