Drain the canned tuna lightly and mix it with the other filling ingredients in a bowl. Divide the mixture into 12 portions.

Place one portion of filling onto a dumpling wrapper. Moisten the edges with water and fold into a triangle, sealing tightly to prevent filling from spilling. Repeat for all wrappers.

Heat half of the sesame oil (1/2 tbsp) in a frying pan over medium heat. Add the dumplings and cook until golden brown on one side. Flip them over, add 1 tbsp of water, cover, and steam for 2 minutes.