When cut into matchsticks, sturdy sweet potatoes can cook quickly, making them ideal for evenings when you’re short on time. Here, they are paired with thinly sliced flank steak and a bold Asian-inspired sauce, which is delicious on a bed of steamed white rice.
Beef and Sweet Potato Stir-Fry
1/2 lb. (250 g.) flank steak
1 1/2 tsp. reduced-sodium soy sauce, plus more for serving
1 1/2 tsp. plus 4 Tbs. (2 fl. oz./60 ml.) peanut oil
1 1/2 tsp. oyster sauce
1 sweet potato, cut into matchsticks
2 small dried red chilies
Salt, to taste
4 green onions, cut diagonally into 1 1/2-inch (4-cm.) pieces
2 garlic cloves, thinly sliced
1-inch (2.5-cm.) piece fresh ginger, peeled and cut into thin slices
Fresh cilantro leaves for garnish
Cooked white rice for serving
Cut the steak in half lengthwise. Cut the halves against the grain into slices about 1/8 inch (3 mm.) thick. In a small bowl, toss together the beef, the 1 1/2 tsp. soy sauce, the 1 1/2 tsp. peanut oil and the oyster sauce. Cover and refrigerate for 2 hours.
In a large, heavy fry pan over high heat, warm 2 Tbs. of the peanut oil. Add the beef and sear for 1 minute without stirring, then stir-fry the beef until the meat is cooked through, about 2 minutes. Transfer to a plate.
Return the pan to high heat and warm the remaining 2 Tbs. peanut oil. Add the sweet potato and dried chilies, season with salt and sear for 1 minute without stirring. Add the green onions and stir-fry until the potatoes are just tender, about 1 minute. Add the garlic and ginger and stir-fry for 1 minute more. Return the beef to the pan and stir-fry until heated through.
Transfer to a large platter and garnish with cilantro. Serve immediately with white rice and soy sauce. Serves 2 to 4.
Find more fresh, seasonal recipes in our cookbook Williams-Sonoma Cooking from the Farmers’ Market.