I use round steak. Buy enough for your family. I usually buy one huge slice with the top and bottom round.
Cut it into serving size portions. Slice a few onions (enough slices so you have one for each piece of steak). Place one layer of meat in the bottom of the crock. Sprinkle with S & P and basil (I use a fair amount of basil). Then place a slice of onion and one bay leaf on top of each serving. Then the next layer of meat... etc. Mix two cans of condensed tomato soup with 1/2 can water and pour over the meat.
Cook on low all day. The "gravy" is good over rice, toast or potatoes. You might want to thicken it with a slurry (I don't).
PS Don't forget to remove the bay leaves before serving. Or at least don't eat them. You can buy the bay leaves cheap at a bulk place like a health food store.