Making the world better, one answer at a time. Almost any large cut of meat in a regular-sized crock pot will be done in 8-10 hours-the more flavor and fall-off-the-bone tenderness you want the longer you cook it.Because of the low temperature and sealed environment food is less prone to burn or become dry. CROCK POT BEEF ROAST.aking the world better, one answer at a time. Almost any large cut of meat in a regular-sized crock pot will be done in 8-10 hours-the more flavor and fall-off-the-bone tenderness you want the longer you cook it.