Heat oil in a large saucepan. Add the red curry paste and cook for about 1 minute, or until fragrant. Stir in the ginger, garlic, and lemongrass, and cook for another 1–2 minutes, stirring frequently to prevent burning.
Next, add the chicken stock and kaffir lime leaves. Bring to the boil, then reduce to a medium simmer and cook uncovered for 15–20 minutes, or until the sauce has slightly thickened.
In a separate frying pan, add another tablespoon of oil, fry aubergine pieces with a sprinkling of salt over medium heat for 5 minutes. Add peppers with a dash more salt and cook for a further 1-2 minutes.
Return to the curry sauce and add the peppers, aubergine, pork, pineapple, and green peppercorns. Increase the heat to medium and cook until the pork is just cooked through. Avoid overcooking, as the pork may become tough and the vegetables too soft.
Remove curry from the heat. Squeeze over the juice of 1/2 lime. Stir in half the Thai basil leaves and spring onions. Divide between bowls and garnish each bowl with the remaining basil leaves. Serve with rice and additional lime wedges.