Heat the cooking oil in a large frying pan or wok on high heat until very hot. Add the green beans and cook for 4-5 minutes, until the beans blister on one side. Turn the beans over and cook for another 2-3 minutes. Try not to move the beans around too much during cooking; they should be slightly wrinkled and softened. Using a slotted spoon, remove the beans from the pan.
In the same pan, add a little more oil if it’s a bit dry. Turn the heat down slightly; add the garlic, green onion, and chili; and cook until fragrant, about 1-2 minutes, taking care not to burn the garlic.
Toss the beans back in and add the salt, sugar, and MSG, if using, and mix thoroughly. Check the seasoning and add more to taste, if needed.
