Beef stroganoff is simple comfort food at it's best.
In a large skillet set to medium high heat add 2 tablespoons of the butter.
Season the beef with salt and pepper and add the beef to the skillet.
Add another two tablespoons of the butter to the skillet. Next add the onions and the mushrooms and sauté for a few minutes to allow the mushrooms to shrink and brown.
Move the mushrooms aside in the skillet and add the remainder of the butter and the flour whisking well, cooking the flour for a few seconds.
Add the beef stock and Worcestershire sauce to the pan and whisk until smooth.
You can also toss the cooked noodles in with the sauce.