Prepare the ingredients: Rinse the mung bean sprouts in water. Finely chop the garlic cloves and set aside. Prepare a small bowl for the marinade sauce. Add all the ingredients, such as fish sauce, soy sauce, chopped garlic, sesame seed oil, and brown sugar. Stir the marinade sauce until the sugar is dissolved.
Blanch the mung bean sprouts: Prepare a large pot, add about 1.5 litres of water, and bring it to a boil. Blanch the mung bean sprouts for one minute, not more than that, to maintain the crunchy texture. Remove the blanched sprouts and rinse in cold running water.
Add the marinade sauce: Transfer the mung bean sprouts to a large bowl, add the marinade sauce, and mix everything together. Sprinkle the sesame seeds to garnish, and serve.