Cut the beef into cubes and place into your slow cooker. Add the prunes and mix together
Add the stock and the beer and a bit of salt. Add the chopped onions and the garlic.
Add the cinnamon sticks and bay leaves, turn on the slowcooker on low and leave to stand for 8 hours. You should be able to separate the meat easily with a fork.
Turn the slowcooker off and taste if it needs extra salt and pepper.
You can eat it straight away but the taste becomes even better after one or two days in the fridge.