Mix stock, oil, soy, brown sugar, garlic, 5 spice and sherry and add to slow cooker. Cut beef into strips, browning is optional. Place into slow cooker.
Cook for first hour on high then turn to low. After 1 hour on low add in the veges, half an hour later add the noodles and their flavour sachet. Cook for a further half hour. Can be left longer than this on low but if doing so don't add the noodles until the last half hour.
This is pictured without the noodles in it as photo was taken before they were added.