Beef Sukiyaki

Ingredients: 2 tablespoons soy sauce 1/3 cup basic brown stock 1/2 cup sweet rice vinegar 1 pound beef sirloin, sliced paper thin 8 small scallions, cut diagonally into 2-inch pieces 1/2 cup bean sprouts 1 cup loosely packed spinach leaves 1 cup mushroom caps 1/2 cup carrots 1/2 cup slice bamboo shoots 1 cup chicken [...]