For the pork, place the roasted peanuts, a few pinches of ground pepper and the dried chillies into a food processor and pulse until coarsely ground. Transfer to a shallow bowl and set aside.
Place the pork steaks in between two sheets of cling film and, using a meat mallet or rolling pin, bash the pork steaks until halved in thickness. Roll the steaks in the soya bean mixture until well-coated, then pat lightly to secure the mixture to the meat, shaking off any excess.
Heat a wok until smoking and add the groundnut oil, then add the pork steaks and cook for 2-3 minutes on both sides, or until golden-brown and cooked through. Remove the steaks from the wok transfer to a warm plate to rest.
For the sweet and sour sauce, place all of the sauce ingredients into a food processor and blend to a smooth paste.
Pour the sweet and sour sauce into the wok used to cook the pork and leave to simmer for 1-2 minutes, or until the sauce has reduced to a thick consistency. Season, to taste, with light soy sauce, rice wine and ground white pepper.
To serve, pour the sauce over the pork and serve with rice and choi sum.