1 thick-cut chuck arm roast
1 lg. jar regular mustard (optional, add some Dijon mustard)
1 lg. jar soy sauce

Put steak in a large roasting pan in the morning. Thickly cover one side with mustard. Generously shake soy sauce over the steak. Poke all over with a large serving fork. Turn steak and repeat. Poke repeatedly all day. The more you poke, the more tender the steak will be. Add more mustard and soy sauce as needed.