Interestingly Mongolian beef is not a traditional Mongolian dish. But is of Taiwanese origin. Still it is tasty
To make the best homemade Mongolian beef, you need to do a couple of things.
1) Marinate the beef with cornstarch and soy sauce. This step is called velveting, and will make the beef, tender, juicy, and well velvety.
2) Don’t over thicken the brown sauce. It shouldn’t be too sticky or gooey.
2 pounds flank steak
1/2 cup cornstarch
3/8 cup oil
1 teaspoon ginger, grated
2 tablespoons garlic, sliced
1 cup water
1 cup soy sauce
1 cup brown sugar
1 teaspoon red pepper flakes
6 large green onion, sliced into thirds
Velvet the Steak (using water method)
Slice up the flank steak
First, make sure the steak slices are dry (pat them dry)and mix them with the corn starch. Using your hands or a spoon, move them around to make sure all pieces are coated. Place beef slices in a strainer and shake off excess corn starch
place beef in a bowl for marinating
Heat half of the oil in a large wok at medium-high and add the garlic and ginger. Immediately add the soy sauce, water, brown sugar and pepper flakes.
Cook the sauce for about 2 minutes and transfer to the bowl with the beef and marinade for 30-45 minutes.
Don’t worry if the sauce doesn’t look thick enough at this point. The corn starch in the beef will thicken it up later.
Next: Remove beef from the marinade. (Reserve the marinade.)
Bring 4 cups of water to boil in a sauce pan. Working in batches poach pieces of meat for about 30 seconds each. (Let the water return to boil between batches.)
Heat up and add the remaining oil to a wok. Add the beef and cook, stirring until it is all browned (this is a quick thing).
Pour the marinade into the wok and let it cook along with the meat.
Now you can choose to cook it down and reduce the sauce or leave it thinner.
Add the green onions on the last minute so the green parts will stay green and the white parts crunchy.