3 tablespoons vegetable oil, divided (I use 2 tablespoons)
1 pound green beans, stemmed and halved on the bias (I just snap them into smaller pieces)
1/4 cup water
1 tablespoon finely grated fresh ginger
½ teaspoon red pepper flakes (optional)
2 tablespoons unseasoned rice vinegar
Ground white pepper (optional)
In a small bowl, stir together the sugar, fish sauce and soy sauce. Set aside.
In a large Dutch oven or 12-inch skillet over medium-high, heat 2 tablespoons of the oil until beginning to smoke. Add the beans and cook, without stirring, until beginning to color, about 3 minutes.
Add the water and immediately cover the pan with a tight fitting lid. Cook until the beans are bright green and barely tender, about 2 minutes.
Clear a space in the center of the pan, then add the remaining 1 tablespoon oil (I don’t add any more oil) to the clearing. Stir in the ginger and pepper flakes and cook until fragrant, about 30 seconds. Pour the sugar-fish sauce mixture into the skillet and cook, stirring occasionally, until the liquid has thickened and coats the beans, about 1 minute.