3/4 pounds rib-eye steak, trimmed of excess fat
1/8 cup soy sauce
1/2 tbsp hot chile sesame oil*
1 tbsp dark brown sugar
3 garlic cloves, minced
1/2 tbsp finely grated peeled fresh ginger
1 medium red onions, halved and cut lengthwise into 1-inch wedges
1/2 green bell pepper, seeds and ribs removed, sliced into 1/2-inch strips
2 tsp vegetable oil
1 small head Boston lettuce, separated into leaves
1. Slice diagonally (across the grain) into 1/8-inch-thick strips. In a small bowl, whisk together the soy sauce, sesame oil, brown sugar, garlic, and ginger. Place the onions and peppers in a small bowl; toss with half the soy marinade. Toss the steak in the remaining marinade; let stand for 15 minutes.
2. Heat 1 tsp of the vegetable oil in a large nonstick skillet over medium-high heat. Add the onions and peppers; cook until softened, about 5 minutes. Transfer to a plate. Wipe the skillet clean with a paper towel.
3. Heat the remaining 1 tbsp vegetable oil over high heat. Cook the meat, turning often, until browned, about 2 minutes. Add the onion mixture. Cook, tossing, until heated through, about 1 minute. Serve with rice and vegetables on the side.
* If you can’t find hot chile sesame oil, add a dash of red pepper flakes to 1/2 tbsp toasted sesame oil.