In a medium bowl, combine the ground pork, water, Shaoxing wine, cornstarch, baking soda, and white pepper. Set aside to marinate while you prepare the rest of the ingredients.
Right before you’re ready to cook, cut the eggplants on an angle into triangular chunks, about 1-inch thick (rotating the eggplant as you cut will give you chunks with sharp angles and a vaguely triangular shape). Don’t let the pieces sit out too long, or they will turn brown.
Heat your wok over medium-high heat until it’s smoking lightly. Pour 3 tablespoons of oil around the perimeter. Spread the eggplant in a single layer in the oiled wok. Reduce the heat to medium. Cook for 7-8 minutes, stirring occasionally until it starts to turn golden, soft, and translucent. (If you have a smaller wok, you can do this step in two batches to ensure the eggplant cooks evenly.) Remove the eggplant from the wok and set on a plate.
With your wok set over medium heat, add the remaining 2 tablespoons of oil. Add the ginger, and cook for 1 minute, until fragrant. Add the garlic. Fry for another minute, and then turn up the heat to high and add the ground pork. Break up the meat and fry it until it’s cooked through.
Stir in the Sichuan peppercorns and the spicy bean sauce. Cook for 1 minute, until the sauce is an even color.
Then add the fermented black beans, chicken stock, chili oil, sugar, and sesame oil. Let this simmer for a minute or so. While that's happening, put a ¼ cup of water in a small bowl with your cornstarch and mix until thoroughly combined.
Stir the eggplant into the sauce. Simmer, covered, for 5 minutes. After 5 minutes, add the cornstarch slurry, and simmer for 1 minute or so to allow the sauce to thicken. Stir in the scallions until they are just wilted, and serve.