Beef and Sweet Potato Stir Fry

Serves 6


1 medium red onion, sliced thin
3 garlic cloves, sliced thin
1½ pound sweet potatoes (about 3 large)
8 ounces snow peas, trimmed
1½ pound boneless beef sirloin or flank steak
6 scallions
1 cup chicken broth
½ cup hoisin sauce
1 tablespoon cornstarch
6 tablespoons peanut oil
3 teaspoons Asian sesame oil


Peel sweet potatoes, cut lengthwise and slice into 18-inch thick slices. Diagonally halve snow peas. Diagonally cut scallions into thin slices. Slice the meat, against the grain, into thin strips similar in size to the sweet potato slices. In a small bowl whisk together broth, hoisin sauce, and cornstarch until combined well. Set aside.
Heat 2 tablespoons peanut oil in a wok or large heavy skillet over high heat until hot but not smoking. Add onion and stir-fry until softened. Add garlic and stir-fry until fragrant; about 30 seconds. Add sweet potatoes and stir-fry until just tender; 6 to 8 minutes. Add snow peas and stir-fry about 2 more minutes. Transfer vegetables to a large bowl.
Add 1 tablespoon peanut oil to wok or skillet and heat until just smoking. Stir-fry half of beef until browned and transfer to bowl with vegetables. Add remaining tablespoon peanut oil and stir-fry remaining beef in same manner, then transfer to bowl.
Add broth mixture to wok or skillet and bring to a boil, stirring constantly. Simmer broth mixture 1 minute. Return beef-vegetable mixture with scallions to wok or skillet and stir-fry until combined and heated through. Season stir-fry with salt and pepper and stir in sesame oil.
Serve stir-fry over rice, garnished with scallions.