Brown the meat in a dry pan on a high heat, then place two sliced red onions in the base of the slow cooker. Put the beef on top of the onions.
Make 400 ml (2 cups) rich beef stock (broth) using a stockpot (or stock cube), pour into slow cooker.
Add the Worcestershire sauce, season the beef with salt and pepper, add 2 tsp dried sage and 1 tsp dried rosemary.
Cook on low for 8-9 hours. To make gravy with the juices, thicken with a paste of cornflour and a little cold water, or make a roux in a saucepan using plain flour and butter, and add the juices to that, then heat and stir constantly until thickened,