Soy Sauce Beef Tri-Tip/Tenderloin

Beef tenderloin or tri-tip (3 lbs)
1/2 cup butter, melted
3/4 cup soy sauce

Preheat oven to 350. Put beef in a shallow glass baking dish. Pour melted butter and soy sauce on top of beef. Cook for 10 minutes, then turn meat over and cook for another 35 - 40 minutes, basting occasionally until internal temp reaches 140 for medium. Add 10 - 15 minutes to have it more done.