Cut the eggplants into 1-inch cubes, leaving the skin on, and pat dry with paper towels to remove excess moisture.

In a small bowl, whisk together 3 tablespoons soy sauce, 1 tablespoon oyster sauce, 1 teaspoon sugar, and 1/4 cup water until the sugar dissolves completely.

Heat a large wok or wide skillet over high heat until smoking hot, about 1 minute.

Add 3 tablespoons vegetable oil and swirl to coat the pan. Add the eggplant cubes in a single layer and cook without stirring for 2 to 3 minutes until golden on one side.

Stir the eggplant and continue cooking for another 3 to 4 minutes until most pieces are golden brown and slightly wrinkled.

Push the eggplant to the sides of the pan and add the minced garlic and sliced chilies to the center. Cook, stirring constantly, for 30 seconds to 1 minute until fragrant.

Pour the prepared sauce into the pan and toss to coat the eggplant evenly. Reduce the heat if the sauce is bubbling too vigorously.

Cook for 1 to 2 minutes more until the sauce reduces slightly and clings to the eggplant, then remove from heat.

Add 1 cup fresh Thai basil and 2 green onions, tossing gently off the heat so the herbs wilt lightly but remain bright and aromatic.