Szechuan Green Beans

1 pound Chinese long beans (used fresh green beans)
1 tablespoon garlic, chopped
1 tablespoon ginger, chopped
pinch red pepper flakes
1 tablespoon dark soy sauce
1/2 teaspoon sugar
1/4 teaspoon salt, or to taste
Pepper to taste, optional
2 tablespoons vegetable or peanut oil for stir-frying, or as needed

Wash the beans, drain thoroughly, and trim the tops and bottoms.
Chop the garlic and ginger.
Heat 1 tablespoon oil over medium heat. Add the beans and stir-fry until they start to shrivel or "pucker" and turn brown (5 - 7 minutes). Add the garlic, ginger, red pepper flakes, soy and sugar. Stir-fry for a few seconds until aromatic and sauce has thickened.