Quick Answer: Can you slow cook already cooked beef?

We love this delicious Leftover Crockpot Roast Beef Stew — and the great thing about it is you cook it in the slow cooker! You just throw everything in the crockpot and let it cook! A few hours on high will do it, or about 5 hours on low. … It’s a great way to use up leftover steak, too.