Open the canned tuna, and drain every drop of oil or juice from the tuna.
Add the drained canned tuna, chopped coriander, minced garlic and ginger, grated onion, egg, and fish sauce in a large bowl.
Use your hand to form them into a patties that is equal to 2 to 3 tablespoon. Make them into a patties around 3 to 4 pieces.
Turn on the gas stove in medium low heat. Add olive oil in the skillet or pan. Once it is hot, add the tuna patties and cook it for 3 minutes on each side or until it turns into a golden brown.