Mongolian Beef Recipe

Slice the meat

Trim any excess fat from the flank steak. Slice the steak thinly across the grain into 1/8–1/4 inch slices. For easier slicing, place the steak in the freezer for 20–30 minutes until slightly firm.

Tenderize and coat

In a bowl, toss the sliced beef with 1 tablespoon cornstarch and the optional 1/4 teaspoon baking soda (if using). Mix until evenly coated. Let rest for 10–15 minutes—this helps create a slightly crisp exterior when cooked.

Whisk together 1/2 cup low-sodium soy sauce, 1/4 cup water, 1/4 cup packed brown sugar, 1 teaspoon hoisin sauce (optional), and 1/2 teaspoon sesame oil in a small bowl until the sugar dissolves. In a separate small bowl, mix 1 tablespoon cornstarch with 1 tablespoon cold water to form a slurry; set both aside.

Peel and finely grate or mince the ginger (about 1 tablespoon). Peel and mince the garlic cloves. Trim and slice 4 scallions into 1–2 inch lengths, separating whites from greens (keep 2 extra scallions reserved for garnish).

Heat a large wok or heavy skillet over high heat until very hot. Add 2 tablespoons vegetable oil and swirl to coat. Working in a single layer and in batches to avoid crowding, add the coated beef slices and spread them out. Let sear undisturbed for about 30–45 seconds, then stir-fry for another 30–60 seconds until browned but not fully cooked through. Transfer seared beef to a plate and repeat with remaining beef, adding the remaining 1 tablespoon oil if needed.

Reduce heat to medium-high. Leave about 1 tablespoon oil in the pan and add the minced garlic and grated ginger; stir-fry 20–30 seconds until fragrant (do not burn). Add the white parts of the sliced scallions and red pepper flakes (if using); stir 15–20 seconds.

Pour the prepared soy-brown sugar sauce into the pan and bring to a simmer. Stir once, then give the cornstarch slurry a quick stir and pour it into the simmering sauce while stirring. Cook 1–2 minutes until the sauce thickens and becomes glossy.

Return the seared beef and any accumulated juices to the pan. Toss thoroughly to coat with the sauce and cook for another 1–2 minutes until the beef is heated through and the sauce clings to the meat. Taste and adjust: add a pinch of salt if needed or a splash of water if too thick.

Turn off the heat and stir in 1/2 teaspoon sesame oil. Add the green parts of the sliced scallions and toss to combine. Transfer to a serving platter and garnish with toasted sesame seeds and the reserved extra scallion slices. Serve immediately over steamed white rice or noodles.