Set the onions and chillies on the side, and cut the chicken up into small chunks. In Thailand, they use minced (that's "ground" for you Americans) chicken for this particular dish, but since I don't have the requisite equipment, I am quite happy to cut it into little bits. Anyway, I messed up a little, and didn't cut the chicken up quite as small as I'd have liked. But it was still good, eventually - this is what it looked like.
   
 
Step 5:

Anyway, put some oil in a wok, heat it up, and when it's good and hot (I use a tiny bit of onion to test) add the onions and chillis.