In a wide pan over medium heat, heat about 3 tablespoons of the oil. Add eggplant and cook until lightly browned. Remove from pan and drain on paper towels.
In the pan, heat the remaining 1 tablespoon oil. Add garlic and chili peppers and cook, stirring regularly, until softened and aromatic. Add vinegar and soy sauce and bring to a boil, uncovered and without stirring, for about 3 to 5 minutes.
Add eggplant and cook, covered, for about 4 to 5 minutes or until tender. Season with salt and pepper to taste. Serve hot.