If fresh spinach is unavailable or too much trouble, 10 oz frozen spinach may be substituted for 2 lb fresh. Trim, wash, and drain spinach. Cut into 1" to 2" widths. Mix miso, soy sauce, and vinegar; set aside. Heat wok over high heat. Add almonds and stir-fry until fragrant and edges turn golden, about 45 seconds. Transfer to plate. Heat oil in wok. Add spinach and ginger and stir-fry just until tender, about 3 minutes. Drizzle with bean mixture. Serve immediately!