Equipment
Ingredients
Beef and Marinade
- 400 g beef flank steak, sliced thinly against the grain
- 15 ml light soy sauce
- 15 ml shaoxing wine
- 5 g cornstarch
- 2 g baking soda
- 15 ml vegetable oil
Aromatics and Vegetables
- 15 g fermented black beans, rinsed and roughly chopped
- 10 g fresh ginger, minced
- 15 g garlic, minced
- 150 g green bell pepper, cut into bite-sized pieces
- 100 g red onion, cut into bite-sized pieces
- 30 ml vegetable oil
Stir-Fry Sauce
- 30 ml oyster sauce
- 15 ml light soy sauce
- 5 ml dark soy sauce
- 5 g granulated sugar
- 60 ml chicken broth
- 5 g cornstarch
- 5 ml toasted sesame oil
Nutrition (per serving)
Nutrition is estimated per serving. Nutrients without complete source data are omitted.
Full nutrition
- Calories
- 328 kcal
- Protein
- 25 g
- Carbohydrates
- 12 g
- Fat
- 19 g
- Fiber
- 2 g
- Sugar
- 4 g
- Sodium
- 1090 mg
- Saturated Fat
- 5 g
- Monounsaturated Fat
- 3 g
- Polyunsaturated Fat
- 1 g
- Cholesterol
- 69 mg
- Potassium
- 595 mg
- Calcium
- 61 mg
- Iron
- 2.4 mg
- Magnesium
- 38 mg
- Phosphorus
- 266 mg
- Zinc
- 4.4 mg
- Vitamin A
- 7 mcg
- Vitamin C
- 33 mg
- Vitamin D
- 0.1 mcg
- Vitamin E
- 0.5 mg
- Vitamin K
- 4 mcg
- Vitamin B6
- 0.8 mg
- Vitamin B12
- 1.2 mcg
- Thiamin
- 0.11 mg
- Riboflavin
- 0.17 mg
- Niacin
- 8.2 mg
- Folate
- 25 mcg
- Water
- 157 g
Sources: Aggregated Public Data, USDA FoodData Central
Method
Place the thinly sliced beef in a mixing bowl. Add the light soy sauce, Shaoxing wine, cornstarch, baking soda, and 15ml of vegetable oil. Toss to coat evenly and let marinate at room temperature for 15 minutes. Use a dedicated cutting board and knife for the raw beef to prevent cross-contamination, and wash hands and surfaces thoroughly with hot soapy water after handling.
In a separate small bowl, whisk together the oyster sauce, light soy sauce, dark soy sauce, sugar, chicken broth, cornstarch, and sesame oil until the cornstarch and sugar are fully dissolved. Set aside.
Rinse the fermented black beans briefly under water to remove excess salt, then roughly chop them. Mince the garlic and ginger, and cut the bell pepper and red onion into uniform bite-sized pieces.
Heat a wok or large skillet over high heat until smoking hot. Add 15ml of vegetable oil, swirling to coat the pan. Add the marinated beef in a single layer and let it sear undisturbed for 1 minute before tossing. Cook for another minute until just browned on the outside. Transfer the partially cooked beef to a clean plate.
Return the wok to high heat and add the remaining 15ml of vegetable oil. Add the chopped bell pepper and red onion. Stir-fry constantly for 2 minutes until the vegetables begin to blister but remain crisp.
Push the vegetables to the sides of the wok. Add the chopped fermented black beans, minced garlic, and minced ginger into the center of the pan. Cook for 30 seconds until highly fragrant, then toss everything together.
Return the seared beef and any resting juices to the wok. Give the prepared stir-fry sauce a quick stir to re-incorporate the cornstarch, then pour it over the meat and vegetables. Toss continuously for 1 to 2 minutes until the sauce bubbles, turns glossy, and evenly coats the ingredients. Ensure the beef reaches a safe internal temperature of 74°C/165°F.
Remove the wok from the heat immediately to prevent overcooking the beef. Transfer to a serving platter and serve hot alongside steamed jasmine rice.
Chef's Notes
- Velveting with a small amount of baking soda alters the pH of the meat. This relaxes the muscle fibers and ensures the beef remains incredibly tender even during a blistering high-heat stir-fry.
- Rinsing fermented black beans removes excess surface salt and allows their deeply savory, complex flavor to shine without overpowering the final dish.
- Mise en place is critical for wok cooking. Have all sauces mixed, aromatics minced, and vegetables chopped before turning on the heat, as the active cooking process takes less than ten minutes.
- For the best wok hei (breath of the wok), cook in batches if your pan is crowded. Overcrowding drops the pan temperature, causing the beef to steam in its own juices rather than sear.
Storage
Refrigerator: 3 days — Store in an airtight container. The vegetables will soften slightly upon reheating.
Freezer: 1 month — Freeze in a sealed container. Thaw overnight in the refrigerator before reheating.
Reheating: Reheat in a skillet over medium-high heat with a splash of water until hot.
Troubleshooting
Beef is tough and extremely chewy.
Cause: Beef was sliced parallel to the muscle fibers (with the grain) or overcooked.
Fix: Cannot be fixed once cooked. Cut into smaller pieces while eating.
Prevention: Always identify the direction of the muscle fibers on the flank steak and slice perpendicular to them. Ensure you do not skip the baking soda marinade step.
Sauce is too watery and pooling at the bottom of the plate.
Cause: Cornstarch was not adequately mixed before adding, or wok heat was too low to activate it.
Fix: Return to high heat and simmer vigorously for another 30 to 60 seconds until thickened.
Prevention: Always stir the sauce mixture immediately before pouring it into the wok, and ensure the liquid comes to a vigorous boil.
Dish is overwhelmingly salty.
Cause: Fermented black beans were not rinsed, or too much soy sauce was added.
Fix: Add a splash of water, a pinch more sugar, or a mild vegetable like sliced zucchini to dilute the salinity. Serve with unseasoned rice.
Prevention: Rinse fermented black beans under cold water before chopping to remove surface salt.
Cultural Context
Douchi, or fermented black soybeans, is one of the oldest known soy condiments in Chinese culinary history, dating back over two millennia. It provides a foundational umami backbone to countless regional dishes, particularly in traditional Cantonese and Sichuan cuisines.
