01 -
Slice the steak thinly against the grain and place in a mixing bowl. Add baking soda, cornstarch, kosher salt, vegetable oil, soy sauce, and mirin. Toss thoroughly to coat all pieces, cover, and refrigerate for at least 1 hour or overnight.
02 -
In a separate bowl, combine oyster sauce, hoisin sauce, soy sauce, and brown sugar. Stir until smooth and set aside.
03 -
Heat vegetable oil in a large wok or skillet over medium-high heat. Working in batches, fry the marinated steak slices for 2–3 minutes per batch until golden brown. Transfer cooked steak to a plate and repeat as needed.
04 -
Add minced garlic, minced ginger, white parts of the green onions, and dried red chilies to the same pan. Sauté on medium heat for 30 seconds until fragrant.
05 -
Pour the sauce mixture into the pan and bring to a simmer. Return the seared steak slices and scatter in the green parts of the onions. Stir to combine, and cook for an additional 5 minutes, allowing the flavors to meld.
06 -
Plate the Mongolian beef over freshly steamed rice and serve immediately.