Perfect Roast Beef

Vegetarian friends look the other way on this one.
It's a meat thing.
I've been making roast beef for years with some good and some not so good results, and found this method of cooking this chunk of beef
absolutely the best way to make it juicy and simply perfect.

Ingredients:
4 lbs top round roast beef
1 onion, cut into thin rings
Worcestershire sauce
garlic powder
black pepper

Directions:
Preheat oven to 500 degrees.
Put the roast in a roasting pan.
Rub roast with some Worcestershire sauce.
Sprinkle with garlic powder and black pepper.
Cut onion into thin rings,
put all over the top and sides of the roast
using toothpicks if necessary.
DO NOT SALT roast, if you do it will dry it out.
Put roast in the oven on the middle rack.
Bake at 500 degrees for 15 minutes, then shut off oven,
and let sit in the oven for 15 minutes per lb.
A four pound cut of beef is in for an additional two hours.
DO NOT under any circumstances open the oven door!
VERY IMPORTANT! You need the warmth of the oven at this time.
After you bake your roast the 15 minutes per lb.
take it out of the oven,
let sit for 15 minutes before serving
to allow juices to distribute in the roast.
A nice beef gravy would go good with this roast.