In a bowl, combine the rice wine, sesame oil, cornflour and 1 tablespoon of the soy sauce.
Slice the pork into discs, about 1cm thick, then toss through the marinade. Set aside.
Slice the white part of the spring onions on the diagonal, then slice the green part into ribbons. Place in a bowl of ice-cold water.
Deseed the peppers, then cut each half into 8 wedges. Peel and very thinly slice the garlic, then slice the chilli on the diagonal. Peel and chop the ginger into matchsticks.
Heat a large wok or large frying pan until smoking hot, add the peppers and fry for 4 minutes, or until slightly charred.
Add 1 tablespoon of the groundnut oil to the wok and stir to coat the peppers. Leave for 1 minute, then transfer the peppers to a plate.
Lift the pork out of the marinade with a large slotted spoon and carefully add to the wok. Stir-fry for 3 to 4 minutes, or until golden, moving it every 20 seconds or so. Transfer the pork to a plate and set aside.
Add the rest of the groundnut oil and the chilli oil to the wok. Quickly add the garlic, chilli, dried chilli (if using), ginger and white part of the spring onion, then stir-fry for 30 seconds.
Stir in the sugar, 3 tablespoons of water and the remaining soy sauce. Bring the mixture to the boil, then return the pork and peppers to the wok. Add the black beans, then stir-fry for 3 minutes.
Meanwhile, toast the sesame seeds in a dry frying pan.
Serve with jasmine rice and garnish with toasted sesame seeds and the green part of the spring onion.