Wash the eggplants thoroughly and cut them into bite-sized cubes. Place the eggplant pieces in a mixing bowl and season with salt and ground black pepper. Toss well so the seasoning is evenly distributed.

Add the cornstarch and mix until the eggplant pieces are lightly coated. The cornstarch helps create a light coating around the eggplant while stir-frying.

Mince the garlic and slice the red onion. Preparing these ingredients before cooking makes the stir-frying process easier because the garlic and onion cook quickly.

Heat the cooking oil in a pan over medium heat. Add the sliced onion and sauté for a few seconds until it starts to soften.

Add the minced garlic and continue sautéing until fragrant. Be careful not to burn the garlic because it can give the dish a bitter taste.

Add the coated eggplant to the pan. Stir-fry gently so the pieces cook evenly and become tender.

Continue cooking until the eggplant starts to soften. If the pan becomes too dry, reduce the heat slightly and continue stirring until the eggplant reaches your preferred texture.

Pour in the soy sauce, oyster sauce, and cooking wine. Stir well to distribute the sauce evenly throughout the eggplant.

Allow the eggplant to cook for another minute or two so it can absorb the savory sauce. The sauce should coat the eggplant without making the dish overly watery.

Add the chili flakes according to your preferred level of spiciness. Stir everything together and taste the dish. Adjust the seasoning if necessary.

Turn off the heat and garnish with chopped parsley if desired. Serve hot with steamed white rice.