BEEF STIR-FRY WITH MUSHROOMS AND SPINACH

1 bag porcini mushrooms
hot water
3 Tbsp. lite soy sauce, plus more for serving
1 Tbsp. dry sherry or Chinese rice wine (optional)
1 Tbsp. cornstarch
1 tsp. sugar
1 lb. boneless sirloin steak, thinly sliced across the grain
2 tsp. vegetable oil
2 tsp. Oriental sesame oil
2 tsp. fresh ginger, minced
1 clove garlic, minced
1 cup scallions, chopped
6 ounces spinach, washed, tough stems discarded

Cover mushrooms with hot water in a bowl. Let soak 15 minutes.

Drain, reserving liquid. Rinse mushrooms under running water. Pat dry and slice. Set aside.

Combine soy sauce, sherry, cornstarch, and sugar in a jar with a tight-fitting lid. Shake vigorously.

Place sliced steak in a mixing bowl. Pour marinade over steak and toss to coat.

Heat vegetable oil and sesame oil in a wok or heavy nonstick skillet over high heat. Stir-fry ginger and garlic 45 seconds.

Add steak and marinade and stir-fry 2 minutes or until steak begins to brown.

Add scallions and mushrooms and stir-fry 2 minutes or until scallions are softened.

Add spinach and reserved mushroom soaking liquid. Stir-fry another 45 seconds. Season to taste with pepper.

Serve with additional soy sauce.