Heat a large wok or skillet over high heat. Season the pork with the salt and pepper. Add the oil to the skillet and once it’s hot, add the pork. Cook until seared and golden brown on all sides, about 6 to 8 minutes. Remove the pork from the wok and place it aside in a bowl. Add the onion, ginger and garlic to the skillet, stirring to toss. Cook until slightly softened, about 5 minutes, stirring occasionally.
In a bowl, whisk together the chicken stock, sugar, soy sauce, cornstarch, vinegar and pepper flakes. Pour it into the skillet and bring it to a boil. Reduce to a simmer and cook for 3 to 4 minutes. Add the pork and red pepper into the wok, tossing to coat and cook for another 2 minutes.
Serve immediately over brown jasmine rice. Top with the cabbage, peanuts, cilantro and a spritz of lime.