Slice 1 green onion into rounds. Thinly slice 1 small onion into strips. And mince the garlic.
Mix sauce: Combine soy sauce, mirin, oyster sauce, sugar, and MSG in a bowl and set aside.
Heat oil in a pan over high heat. Add the eggplant, sprinkle with salt, and cook until golden brown on all sides. Remove and set aside.
In the same pan, add a fresh drizzle of oil(1tbsp). Add the green onion, 1 tablespoons minced garlic, and onion. Stir-fry over low heat until fragrant.
Once the onion turns slightly translucent, add ground pork or beef and stir-fry over medium-high heat.
Once the meat is no longer pink, pour in the prepared sauce and stir-fry everything together.Add water to the pan and bring to a boil.
Mix potato starch and water together to make a starch slurry. You don't need to add it all at once, add it gradually to the stir-fry a little at a time, stirring as you go, until you reach your desired consistency.
Once the sauce thickens to a glossy consistency, add the seared eggplant back in and toss quickly over high heat for under 30 sec.
Spoon rice into bowls and top with the eggplant and meat mixture.Garnish with sliced green onion and serve immediately.
For the starch slurry, add it gradually rather than all at once. The goal is a thick, glossy sauce that coats everything. A cooking video can be very helpful for gauging the right consistency.