Beef and Onion Stir-Fry
Thinly sliced flank steak and onions in a savory sauce. Sear the beef in batches so each piece has room in the pan.

Method
Slice the flank steak diagonally into thin slices.
Combine the marinade ingredients, toss with the steak and marinate for 15-30 minutes.
Drizzle oil in a skillet. Stir-fry the yellow onion and white parts of the green onions for a few minutes, until beginning to soften. Remove and set aside.
Sear the steak in the same pan for about 2-3 minutes per side. Work in batches without overlapping the pieces; I cooked mine in about three batches.
Combine the stir-fry sauce ingredients. Return all the beef and cooked onions to the pan with the garlic, green onion tops and sauce.
Simmer, stirring, just until the sauce thickens. Serve over rice or your chosen base.
Alexa's notes
My take on the Mongolian beef we grew up eating. Savory, tender, and so delicious!
- beef
- stir fry
- dinner
With love, Alexa
With Love, Alexa Recipes from Alexa's kitchen
Beef and Onion Stir-Fry
Ingredients
- 1 lb flank steak
- Oil, for the pan
- Rice or your choice of base, to serve
Marinade
- 1 tbsp soy sauce
- 1 tbsp sesame oil
- 2 tsp rice vinegar
- Olive oil, a drizzle
- 1½ tbsp cornstarch
- ½ tsp baking soda
Stir-fry sauce
- 1 tbsp rice vinegar
- 2 tsp sesame oil
- 1½ tbsp oyster sauce
- 1 tbsp soy sauce
- 1 tsp cornstarch
- 1 tsp black pepper
- 3 tbsp water
- 1 tbsp brown sugar
- 1 tbsp chili crunch oil
Vegetables
- ½ yellow onion, thinly sliced
- 4 green onions, cut into larger pieces, whites and greens separated
- 4 garlic cloves
Method
- Slice the flank steak diagonally into thin slices.
- Combine the marinade ingredients, toss with the steak and marinate for 15-30 minutes.
- Drizzle oil in a skillet. Stir-fry the yellow onion and white parts of the green onions for a few minutes, until beginning to soften. Remove and set aside.
- Sear the steak in the same pan for about 2-3 minutes per side. Work in batches without overlapping the pieces; I cooked mine in about three batches.
- Combine the stir-fry sauce ingredients. Return all the beef and cooked onions to the pan with the garlic, green onion tops and sauce.
- Simmer, stirring, just until the sauce thickens. Serve over rice or your chosen base.
Notes
My take on the Mongolian beef we grew up eating. Savory, tender, and so delicious!