Bring water to a boil in a saucepan or kettle. Remove from the heat, add the noodles, and let them cook for 4 minutes. Rinse with cold water and drain in a colander.
Peel and grate the carrot (or cut into fine sticks with a large knife).
Wash the salad leaves and pat them dry. Rinse the mint. Chop both finely with a knife (or scissors).
Coarsely crush the cashew nuts with a large knife.
Mix all ingredients in a small bowl with a few drops of lime juice, nuoc-mâm, and oil.
No need to add salt, as nuoc-mâm (or soy sauce) already contains it.