To prepare a stir fry beef spinach with noodles beef recipe, you will first need to prepare the noodles. Heat 1 tablespoon of vegetable oil over medium heat. Add 2 tablespoons of minced garlic to the oil and saute until the garlic is fragrant, about 1 minute. Stir in 1 cup of chopped fresh spinach. Cook, stirring frequently, until spinach is wilted, 1 to 2 minutes. Remove from heat and add 2 cups of water. Bring to boil. Reduce heat to medium-low and simmer, covered, for 5 to 10 minutes, or until noodles are tender, but not mushy. Serve with sour cream, if desired.