Break the vermicelli into small pieces and place in a deep-sided dish. Cover with hot tap water and soak for ten minutes; drain.
Whisk together the soy sauce, brown sugar and boiling water; pour over the drained noodles; allow to soak 2 minutes.
Pour the vegetable oil into a frypan and place over medium heat. Add the noodles and soy sauce mixture to the frypan and cook and stir until hot; about 5 minutes. Sprinkle sesame seeds over the noodles just before serving.