We have a slow cooker which was given to us as a wedding present 42 years ago. We use it regularly and it is great for stews made using shin of beef or beef rib trim etc. Basically any fatty cheap cut of meat. I caramelise onions and then add garlic and finely sliced ginger. Bung that in the slow cooker set to low. Brown the meat in olive oil and put that in. Deglaze the pan with some red wine (I sometimes use port) and pour that in on top of the meat. Pour in half a pint of good beef stock and season with salt, pepper and smoked paprika or pimenton.
You can add thinly sliced carrots and raw mushrooms. Root vegetables generally don't cook in a slow cooker but you can boil potatoes and then put them in, they absorb the juices but they are best if cut fairly small.
Cook for at least 4 hours and up to 8 hours. Before serving I ladle out some of the liquid and thicken it with cornflour (just like making gravy) and pour it back into the stew.
Flavour enhancers like Worcestershire sauce and dark soy sauce can be added.