Step 1: After the water boils, add the bonito flakes, cook on medium heat for 10-15 minutes until light yellow, then add Japanese soy sauce, mirin, cooking sake/sake to make the soup base.
Step 2: Add a small amount of olive oil to the wok, fry the hard bean curd until golden brown and set aside.
Step 3: Fry the onion in a frying pan until golden brown, then add the beef slices, and fry the beef slices over low heat until they are medium and set aside.
Step 4: Put all the ingredients in the soup base and enjoy.
