Fake Sukiyaki - cooking recipe

Ingredients

1/2 pound thinly sliced roast beef, cut into strips
1 bunch fresh spinach, rinsed and stemmed
12 ounces fresh button mushrooms, halved
1 (10.75 ounce) can beef stock, divided
1/2 cup thinly sliced onion
3 tablespoons sake, or to taste
3 tablespoons soy sauce, or to taste

Preparation

In a wok over high heat, combine 1/4 cup of the beef stock, soy sauce, and sake. Add onions and mushrooms; fry until onions start to soften. Add the strips of beef and remaining beef stock, and cook, stirring constantly, for 2 minutes. Add spinach, cover, and cook for 3 minutes, until spinach is wilted, but not fully cooked. Adjust seasonings to taste, and serve over udon or ramen noodles.