This is a rather nice recipe, a bit different from your run of the mill one, with unusual ingredients that can easily be replaced with the version in brackets.
22 open portabello mushrooms, washed and patted dry
1 tablespoon peanut oil
3 cloves garlic, minced
1 cup finely diced daikon (to provide crunch, can replace with celery or water chestnuts)
3 tablespoons mirin (rice wine or cooking sherry)
1/2 teaspoon salt
1/2 teaspoon ground white pepper
1 1/2 cups panko (breadcrumbs)
1 tbls toasted sesame oil, plus extra for greasing the pan / garnish
2–4 tablespoons water
1/2 cup finely chopped scallions, plus extra for garnish
3 tablespoons toasted sesame seeds
Preheat the oven to 350°F
First, remove the stems from the mushrooms. An easy way to do this is to cup one in your writing hand, stem up, and gently but firmly twist and pry the stem out. Then use a small spoon to
remove any remaining stem. Do not discard the stems; chop them up small and set them aside. It’s common to break a mushroom or two, which is why the recipe calls for twenty-two mushrooms but stuffs twenty. If one breaks and can’t be used, just chop it up along with the stems.
If you don't break them whilst removing the stem, then finely chop the two extras anyway.
Preheat a large frying pan over a medium heat. Pour in the peanut oil and sauté the chopped mushroom for about 3 mins, until some moisture has released. Add the diced daikon (celery etc) and cook for 5 more minutes, stirring often. Add the garlic and cook for a minute longer.
At this point, lots of moisture should be released from the mushrooms. Add the mirin (rice wine), salt, and white pepper, and cook for about 2 minutes. Turn off the heat and add the panko (breadcrumbs) in 1/2-cup batches and stir, alternately adding the sesame oil and splashes of water (up to 4 tablespoons) until all the bread crumbs are moist. The mixture should be crumbly but, when you press some between your fingers, it should hold together. Mix in the scallions and adjust the salt to taste.
Grease a baking sheet with a little sesame oil. Stuff each mushroom with the filling and place on the baking sheet. To stuff them, place a little of the filling into the mushroom crevice and then add another tablespoon on top of that, pressing firmly to form a mound.
Bake for 20 minutes. To serve, sprinkle the toasted sesame seeds over the mushrooms and drizzle with a little sesame oil, if desired.
Tip: To toast sesame seeds, preheat a small pan over medium-low heat. Pour in the sesame seeds and toast them, stirring often, for about 3 minutes. Once browned, immediately remove them from the pan to prevent burning
Garnish with extra chopped scallions, placing them on a bed of raw spinach leaves.