Blanch the green beans in boiling water for 2-3 minutes until slightly tender-crisp. Immediately transfer to an ice bath to stop cooking and maintain their vibrant green color.
Drain the green beans thoroughly and pat them dry with paper towels. This step is crucial for achieving a crispy texture.
Heat vegetable oil in a wok or large skillet over high heat. Add the minced garlic and stir-fry until fragrant (about 30 seconds).
Add the blanched green beans to the wok and stir-fry for 3-4 minutes, tossing constantly, until they are blistered and slightly charred.
In a small bowl, whisk together the soy sauce, sesame oil, sugar, and salt. Pour the sauce over the green beans and stir-fry for another minute to coat them evenly.
Transfer the green beans to a serving plate and serve immediately.
Notes
Adjust the amount of soy sauce and sugar to your preference. For a spicier kick, add a pinch of red pepper flakes to the sauce.