Tear the lettuce into large pieces.
Place half of the lettuce in a frying pan.
Add the shimeji mushrooms.
Add the pork slices without overlapping.
Add the remaining lettuce and pork.
Sprinkle with salt and pour in the sake.
Cover and steam over medium heat for 6–7 minutes.
Lightly drain the excess liquid.
Pour the sauce over the top and enjoy.
