Beef & Asparagus Stir-Fry

1-1/2 lb sirloin steak, cut into thin strips
Salt and freshly ground black pepper, to taste
1/4 cup Hoisin sauce
2 Tbsp dry sherry
1 tsp chili oil
1/4 cup peanut oil
1 yellow onion, thinly sliced
3/4 lb slender asparagus, trimmed and cut on the diagonal into 1-inch pieces
3 garlic cloves, minced
1/4 tsp red pepper flakes
Steamed rice for serving

Lightly season the beef with salt and black pepper. In a small bowl, stir together the Hoisin sauce, sherry, chili oil and 1/2 cup water. Set aside. In a wok or large fry pan over high heat, warm the peanut oil. Working in batches if needed to avoid crowding, add the beef and cook, turning once or twice, until lightly seared, 2 to 3 minutes. Using a slotted spoon, transfer to a plate. Add the onion and asparagus to the pan and cook until tender-crisp, 2 to 3 minutes. Add the garlic and red pepper flakes and stir-fry for 15 seconds. Return the meat and any juices from the plate to the pan, add the Hoisin mixture and stir well. Simmer briefly until heated through. Divide the rice among shallow bowls, top with beef and asparagus, and serve immediately. Serves 4.