Wash the konjac thoroughly under running water and cut it into bite-size pieces.
Cut the onion and green onion into bite-size pieces.
Add cooking oil to a pan and stir-fry the green onion to bring out the aroma.
Add the onion and stir-fry together.
Add the konjac and stir-fry together.
Add the black bean sauce and stir-fry well, mixing thoroughly.
When all the ingredients are well combined, transfer to a plate to finish.