Mongolian Beef

5 from 5 votes

Mongolian beef with tender flank steak in a sweet and salty sauce that goes thick and glossy. My copycat of the PF Chang's dish I always order.

Prep Time20

Cook Time15

Marinate Time1

Total Time1 35

Course: Main Course

Cuisine: Chinese

Servings:

Calories: 539kcal

Author: Jennifer Fishkind

Ingredients

Beef Marinade

1 pound flank steak
1 tablespoon canola oil
1 tablespoon water
2 teaspoons low-sodium soy sauce
1 tablespoon cornstarch
½ teaspoon baking soda

Stir-Fry

⅓ cup canola oil
⅓ cup plus 1 tablespoon cornstarch divided (⅓ cup to coat the beef and 1 tablespoon for the slurry)
½ cup low-sodium soy sauce
½ cup light brown sugar packed
⅓ cup plus 1 tablespoon water divided (⅓ cup for the sauce and 1 tablespoon for the slurry)
1 tablespoon grated garlic
1 tablespoon grated ginger
1 teaspoon sesame oil
¼ teaspoon red pepper flakes (plus more to taste)
¼ cup sliced green onions cut on the diagonal into ¼ to ½-inch pieces (plus more for garnish)

Instructions

Beef Marinade

Slice the flank steak against the grain into long thin pieces (about ¼-inch thick by 3 to 4-inches long and ½-inch wide). All the pieces should be as uniform in size as possible for even cooking.
1 pound flank steak
Place the sliced beef into a bowl with the canola oil, water, soy sauce, cornstarch, and baking soda. Toss all the ingredients together to fully coat the beef. Cover and marinate at room temperature for 1 hour before frying.
1 tablespoon canola oil, 1 tablespoon water, 2 teaspoons low-sodium soy sauce, 1 tablespoon cornstarch, ½ teaspoon baking soda

Stir-Fry

Heat the canola oil in a large (12-inch) heavy-bottomed skillet over medium-high heat.
⅓ cup canola oil
Add ⅓ cup cornstarch to the bowl of marinating flank steak. Toss to coat, then gently shake off any excess cornstarch before adding the beef to the hot oil.
⅓ cup plus 1 tablespoon cornstarch
Once the oil is hot (it should shimmer and slightly ripple when ready and a small piece of beef should sizzle immediately when added), add half the coated flank steak to the skillet in an even layer. Fry for 2-3 minutes on the first side then flip and fry on the second side for an additional 2-3 minutes or until the flank steak strips are crispy, golden brown around the edges and no pink remains.
Remove the fried flank steak using a slotted spatula and place onto a paper towel-lined plate.
Add the remaining half of the coated flank steak to the skillet and fry for 2-3 minutes per side. Remove and place onto the paper towel-lined plate with the first batch of fried flank steak.
Pour off all but 1 tablespoon of the cooking oil and reduce the heat to medium.
Whisk in the soy sauce, brown sugar, water, garlic, ginger, sesame oil, and red pepper flakes and bring the sauce to a boil.
½ cup low-sodium soy sauce, ½ cup light brown sugar, ⅓ cup plus 1 tablespoon water, 1 tablespoon grated garlic, 1 tablespoon grated ginger, 1 teaspoon sesame oil, ¼ teaspoon red pepper flakes
In a small bowl whisk together the remaining 1 tablespoon cornstarch and 1 tablespoon water until the cornstarch is fully dissolved. Pour the slurry into the bubbling sauce and cook for another 1-2 minutes or until glossy and thick enough to coat the back of a spoon.
Turn off the heat to the skillet, add the reserved fried flank steak and ¼ cup sliced green onions, tossing to evenly coat all the steak pieces with the thickened sauce and serve while hot.
¼ cup sliced green onions

Video

Notes

Slicing: Put the flank steak in the freezer for 30 to 45 minutes, still in its packaging, before you slice it. It firms up just enough to cut thin, clean slices. Use a very sharp knife, and slice against the grain. Flank steak is not the same thickness end to end, so slice some pieces in half lengthwise to keep everything close to uniform. Uniform pieces cook evenly.
The slurry is not optional. The cornstarch on the beef gets used up in the frying, so it will not thicken your sauce. Whisk the reserved tablespoon of cornstarch with a tablespoon of water in a separate small bowl until it dissolves, then stir it into the bubbling sauce. That is what makes it glossy.
Fry in two batches. Crowding the pan drops the oil temperature and steams the beef instead of frying it.
Heat: A quarter teaspoon of red pepper flakes is a balance of sweet and warm that works for most people. Add more if you want it hotter. Taste the sauce before the beef goes back in.
Extra sauce: Double all the sauce ingredients and the slurry. It takes a couple of extra minutes to thicken, so let it simmer until it coats the back of a spoon.
Make ahead: Slice and marinate the beef earlier in the day and dinner comes together in about 15 minutes. Do not fry the beef ahead. The coating softens as it sits.
Storage: Airtight in the refrigerator up to 3 days. Reheat in a skillet over medium-low with a splash of water. I do not recommend freezing. The fried beef gets too soft once frozen and thawed.

Nutrition