Sweet, sour, & crispy mushrooms

Directions

Prepare the batter and the mushrooms

1. Add ½ cup potato starch and 2 cups of water to a bowl and mix well. Do not mix again; just let it sit until the starch settles to the bottom of the bowl, about 30 minutes to 1 hour.
2. Drain the mushrooms and remove the stems. Save the stems and the water to make stew someday (like doenjang-jjigae).
3. Slice each mushroom a few times into bite size pieces. Transfer to a bowl.
4. Add 2 teaspoons soy sauce and the ground black pepper. Mix well and cover and refrigerate while you prepare the other ingredients.

Coat the mushrooms and fry

1. When ready to cook, heat 1½ inches vegetable oil in a large, deep pan over medium-high heat until the temperature reaches 330º to 340º F, about 8 to 10 minutes.
2. Meanwhile, remove the mushrooms from the refrigerator, sprinkle with 1 tablespoon of the potato starch, and mix well by hand to coat evenly.
3. Pour off the water from the starch mixture, so you are left with the solidified starch at the bottom of the bowl. Add the egg white (or about 1 tablespoon water for the vegan version) to the soaked starch and stir together with a spoon until smooth.
4. Add the starch mixture to the mushrooms and mix by hand.
5. Working in batches, gently drop the mushroom pieces into the oil. They will puff up and float to the surface.
6. Cook, stirring occasionally, until light brown and a little crunchy, about 8 minutes. If the mushroom pieces have stuck together in the oil, gently separate them with tongs and a slotted spoon.
7. Transfer the fried mushrooms to a strainer set over a bowl to drain. Reserve the oil.

Make the sauce

1. Combine 1 tablespoon potato starch and 2 tablespoons water in a small bowl and mix well. Set aside.
2. Heat the vegetable oil in a large skillet over medium high heat. Add onion, stirring with a wooden spoon for 1 minute until the onion looks half translucent.
3. Reduce the heat to medium and add 1 cup water, the pineapple juice, salt, soy sauce, sugar, and vinegar. Stir well until the sugar is melted and bring to a boil.
4. Stir the starch slurry with a spoon and gradually stir it into the boiling sauce. Cook until the sauce is thick and shiny, 1 to 2 minutes. Remove from the heat.

Fry the mushrooms again

1. Reheat the vegetable oil over medium-high heat until the temperature reaches 330-340º F.
2. Add all the mushrooms to the hot oil and fry, stirring with tongs, until all the pieces are golden brown and very crunchy, about 5 minutes.
3. Transfer to a strainer set over a bowl to drain the excess oil. Arrange on a large platter.

Serve

1. Reheat the sauce over high heat until bubbling. Add the nectarine, pineapple, and cucumber and stir for 1 to 2 minutes, until the sauce comes back to a boil.
2. Remove from the heat and stir in the sesame oil. Pour the sauce over the fried mushrooms. Serve right away.

Tips for making ahead and reheating

Make ahead

If you want to serve this dish later, fry the mushrooms only once, let them cool, and refrigerate them in a container. Prepare the sauce ahead of time, too, and refrigerate it in a separate container. When you are ready to serve, fry the mushrooms a second time as directed above. Reheat the sauce in a pan, pour it over the freshly fried mushrooms, and serve.

Leftovers

Refrigerate any leftover mushrooms with the sauce. Reheat them in the microwave, or warm them slowly in a pan over low heat, stirring as they heat. If they start to scorch, add about 1 tablespoon of water to the pan and stir well. Continue heating until hot.