How you slice your steak for a stir-fry is so important, and plays a huge role in how tender your meat will end up. The general wisdom is that you want to be slicing across the grain of your meat.

If you take a look at your steak, you should be able to see the grain running in a certain direction. Should you cut with it, your pieces will have long grains running across their surface area, making them harder for you to chew. Take your knife and cut across it instead, and you’ll immediately see the difference in how your slices behave. 

For bigger pieces like rump steak, where the meat almost separates into sections with their own grain, I would suggest dividing these sections up firstly. Once that’s done, treat each section as a separate cut with its own grain direction. Check the video above to see what I mean.

Oh, and very importantly: keep your slices THIN. No more than 3mm (⅛”) is what you should be aiming for.