Cut off the heads of the sanma fish, divide into thirds, remove the innards, rinse with water, and pat dry.

Trim the base of the maitake mushrooms and separate them into smaller pieces. Slice the sudachi into rounds.

In a pot, combine all seasoning ingredients and bring to a boil over medium heat. Once boiling, pour the mixture into a tray and set aside.

Heat salad oil in a frying pan over medium heat. Add maitake mushrooms and sauté until softened, then remove. In the same pan, cook the sanma fish on both sides until golden and cooked through.