Ma Po Eggplant in Garlic Sauce

Name: Ma Po Eggplant in Garlic Sauce
Ingredients: 1 pound ground pork, preferably from the shoulder; 2 tablespoons rice vinegar; 1 tablespoon sambal oelek or other Asian chile sauce; 1 tablespoon cornstarch; 1/4 cup soy sauce; Six 8-ounce Asian eggplants, halved lengthwise; 1 tablespoon peanut oil, plus more for brushing; Kosher salt; 2/3 cup chicken stock or low-sodium broth; 1/4 cup dry sake; 1 1/2 tablespoons sugar; 1 tablespoon toasted sesame oil; 1 teaspoon chile-bean sauce, such as Lee Kum Kee Toban Djan; 3 scallions, minced, plus thinly sliced scallions, for garnish; 4 garlic cloves, minced; 1 1/2 tablespoons minced peeled fresh ginger; Steamed rice, for serving