Preheat the oven to 220°C with a rack set on the middle shelf.
Use a sharp paring knife to lightly score the flesh of each aubergine 6 to 8 times. Place the on a baking sheet and toss with 2 tablespoons of the oil and season liberally with salt and pepper. Place the aubergine, cut-side down, and bake until the aubergine starts to soften and the skin starts to brown, about 15 minutes. Use a large offset spatula to gently flip the aubergine over and bake until the flesh is completely softened and light golden brown, about 15 more minutes.
Meanwhile, make the pork: Heat the remaining oil over medium-high heat in a large saute pan. Add the pork and 1/4 teaspoon salt. Cook, breaking up the meat, until lightly browned and no longer pink, about 5 minutes. Add the spring onion whites, garlic and ginger and cook for 2 minutes, stirring constantly. Stir in the chili-garlic sauce, soy sauce, vinegar, 1/2 cup water and half of the scallion greens. Simmer over medium-low heat for 10 minutes, stirring occasionally.
To serve, spoon the pork over the roasted aubergine and garnish with the remaining spring onion greens. Serve with steamed rice.