Stir-frying beef is fast and economical. I used tri-tip here, but rump, skirt, flat iron, sirloin or Scotch fillet could be used in its place. Usually I’ll trim off any silver skin, then put the beef into the freezer
for 30-60 minutes. This helps with slicing the beef thinly. Any seasonal vegetables could be added here – I tend to quickly blanch vegetables that take a longer time to cook such as broccoli and cauliflower to make cooking in the wok faster.