Ingredients

1 tablespoon plus 1/4 cup water
¼ teaspoon baking soda
1 pound tender steak{beef tenderloin tails, ribeye, or flank steak} trimmed, cut into 1-inch squares
3 tablespoons soy sauce, divided
3 tablespoons dry sherry or Chinese rice wine, divided
3 teaspoons cornstarch, divided
2 ½ teaspoons packed light brown sugar, divided
1 tablespoon oyster sauce
2 teaspoons rice vinegar
2 teaspoons toasted sesame oil
1/2 teaspoon coarsely ground pepper
3 tablespoons plus 1 teaspoon peanut oil, divided
1 red bell pepper, stemmed, seeded, and cut into 1-inch squares
1 green bell pepper, stemmed, seeded, and cut into 1-inch squares
6 scallions, white parts sliced thin on a bias, green parts cut into 2-inch pieces
3 garlic cloves, minced
1 tablespoon grated fresh ginger

Directions

Combine 1 tablespoon water and baking soda in a medium bowl. Add beef and toss to coat. Let sit at room temperature for 5 minutes.

Whisk 1 tablespoon soy sauce, 1 tablespoon sherry, 1½ teaspoons cornstarch, and ½ teaspoon sugar together in a small bowl. Add soy sauce mixture to beef, stir to coat, and let sit at room temperature for 15 to 30 minutes.

Stir-fry Sauce
Whisk remaining ¼ cup water, remaining 2 tablespoons soy sauce, remaining 2 tablespoons sherry, remaining 1½ teaspoons cornstarch, remaining 2 teaspoons sugar, 1 tablespoon oyster sauce, 2 teaspoons vinegar, 2 teaspoons sesame oil, and ½ teaspoon pepper together in the second bowl.

Heat 2 teaspoons peanut oil in a 12-inch nonstick skillet over high heat until just smoking. Add half of the beef in a single layer. Cook without stirring for 1 minute. Continue to cook, stirring occasionally, until spotty brown on both sides, about 1 minute longer. Transfer to a bowl. Repeat with remaining beef and 2 teaspoon oil.

Return skillet to high heat, add 2 teaspoons peanut oil, and heat until beginning to smoke. Add bell peppers and scallion greens and cook, stirring occasionally, until vegetables are spotty brown and crisp-tender, about 4 minutes. Transfer vegetables to bowl with beef.

Return now-empty skillet to medium-high heat and add the remaining 4 teaspoons vegetable oil, scallion whites, garlic, and ginger. Cook, stirring frequently until lightly browned, about 2 minutes. Return beef and vegetables to skillet and stir to combine.

Whisk sauce to recombine. Add to skillet and cook, stirring constantly, until sauce has thickened, about 30 seconds. Serve over rice