I’m not sure how the place you go to usually does it but I start by simmering dried chilies, smashed garlic, sliced ginger and Sichuan peppercorns in oil over low heat while the green beans cook. I like to get it nice and spicy. Strain the oil and crank the heat up to high and then finish off the green beans trying to get some flame licking the oil as you toss (this is def a more advanced technique). Then add back in the pepper, garlic and gingeralong with like 2tsp each of soy sauce and shaoxing wine. About a tsp each of salt and sugar to taste and a sprinkle of red chili flakes if you want. That’s a pretty tradition preparation but it gets done differently everywhere.

If you really want more wok hei you can hit it with a blow torch right at the end, just be careful not to start a grease fire.