Rinse 1 ounce dried gosari (30 grams) in cold water a few times and add to a large heavy pot.
Add 4 quarts (16 cups) water. Cover and cook for 1 hour over medium high heat.
Open and stir the cooked gosari a few times with a wooden spoon and cover.
Turn off the heat and let it sit in the hot water for 3 hours with the lid closed.
Drain and rinse in cold water, changing water a few times. The gosari will expand to 11 ounces.
Soak in a bowl of cold water for at least 1 hour, up to overnight, and drain.
Bring 8 cups of water to a boil. Blanch the softened gosari for 30 seconds, stirring with a wooden spoon to remove any fishy smell.
Drain and cut the gosari into bite size pieces.
Transfer the gosari to a bowl and mix with the soy sauce and perilla seeds oil.
Heat a frying pan or a skillet. Add the vegetable oil and swirl to coat evenly.
Add the marinated gosari. Gently stir it with a wooden spoon or long chopsticks for about 5 to 6 minutes until almost all of the liquid is evaporated.
Remove from the heat and stir in the sesame oil and ground sesame seeds.
Transfer to a plate and sprinkle more sesame seeds over top. Serve with rice.
