Wash the green beans thoroughly under cold running water to remove dirt and ensure they are crisp.

Trim the ends off the green beans using a knife.

Heat 3 tablespoons vegetable oil in a large skillet or wok over medium-high heat until the oil is shimmering.

Add the trimmed green beans to the hot skillet and stir-fry for 3 to 5 minutes until they are bright green and slightly tender.

Add the minced garlic to the pan and stir-fry for 30 seconds until fragrant.

Pour in 2 tablespoons soy sauce, 1 teaspoon sesame oil, and 1 teaspoon sugar; stir and cook for 1 minute until the sauce coats the beans.

Season with salt and pepper to taste and stir to combine.

Remove from heat and serve immediately while hot and crisp.