Beef Teriyaki

2 pounds top blade steak (or 1 1/2 pounds flank steak) slice thin
2 T. vegetable oil
1/2 C soy sauce
1/2 C sugar
2 T mirin
2 t. cornstarch
2 t. grated fresh ginger
1 garlic clove, minced
1/8 t. red pepper flakes
2 scallions, sliced thin

Pat steak dry with paper towel.  Heat 1 T. oil in skillet until just smoking. Brown half steak on both sides (5 mins. total) Transfer to clean bowl, andd second T of oil and brown the rest of the meat.

Whisk soy sauce, sugar, mirin, cornstarch, garlic, and red pepper flakes together. Add sauce to skillet, return to medium-high heat and simmer, scraping up any browned bits, until thickened, about 2 mins.

Add steak to skillet and cook until steak is heated through (1 minute).  Transfer to serving dish and sprinkle with scallions.

*It is important to cut your meat as thin as possible and against the grain.
This is delicious. My kids all love it.
From the editor's of Cook's Illustrated.