I've been cooking a 2.5lb pot roast in the slow cooker for 3 hours on low. It appears cooked, but it's tough. If I cook it longer will it get more tender or is it ruined?
It needs to go much longer. Possibly 4 hours or more. The collagen needs to break down and then the tender will happen. What type of roast is it?
Susan is right. 4-5 hours more is what you're going to need when cooking on low.
Yup, it needs go go a lot longer, but make sure there is quite a bit of liquid in the cooker (you can add more broth if you need to). Without it you'll end up with shoe leather.