Blot off any excess moisture from the pork using a paper towel. Season it with salt and pepper. Heat 1 tablespoon neutral oil in a large skillet or wok over medium-high heat. Add the pork and cook in an even layer for 8–10 minutes until well-browned and cooked through. Transfer to a plate.
Cook the egg:
Pour the egg mixture into the skillet and let it cook untouched for 1–2 minutes. Once the egg is partially set, break it into big pieces using a spatula or spoon. Once the egg cooks through, transfer it to a bowl and let it cool.
Once cool enough to handle, you can finely chop the egg or leave it in big pieces, depending on your preference.
Make the sauce:
Before you fry the vegetables, combine all the sauce ingredients in a small bowl and whisk until the miso melts. Taste and add more of any ingredients until the sauce reaches your desired sweetness, spiciness, and saltiness.
Fry the mushrooms:
If the skillet or wok seems dry, add another drizzle of oil and let it heat up over medium-high. Once hot, add the beech mushrooms and cook, turning occasionally, for 5–7 minutes until they turn golden brown.
Fry the remaining vegetables:
Add the scallions and red bell pepper and toss to combine. Cook for 3–4 minutes.
Add the cabbage and fry, stirring regularly, for 2–3 minutes until completely wilted.
Finish the rice:
Add the pork and egg to the skillet and toss to combine. Fold in the day-old rice and toss to combine. Cook, stirring occasionally, for 3–5 minutes to warm the rice through. Some bits of rice on the bottom should begin to crisp up.
Pour the sauce into the skillet and immediately toss to coat. Continue tossing to coat the rice for 1–2 minutes. Taste, season, and remove from the heat as soon as the rice absorbs the sauce.
To serve:
Spoon the rice onto a serving platter and sprinkle with the reserved minced scallions. Enjoy!
Notes
If you don't have day-old rice, boil up a pot of rice before beginning the recipe.Use 1 cup of white rice, 2 cups of water, and a pinch of salt. Bring to a boil, reduce the heat to low, cover, and simmer for 15 minutes. Turn off the heat and let stand for 5 minutes.Transfer the cooked rice to a mixing bowl or baking sheet. If using a mixing bowl, use a spatula to push the rice up the sides of the bowl to get it into an even layer as much as possible. If using a baking sheet, simply flatten the rice into an even layer. Transfer the rice, uncovered, to the freezer for 15 minutes. This will remove excess moisture, giving the rice a texture that is akin to day-old rice.