What's the best order to add ingredients to a Stir Fry?
I always go in this order:


Garlic/ginger/chili/spring onion whites


This is to infuse the cooking oil with these flavours.  Cook for short amount of time ~30secs.


onions/peppers/carrots/harder veg


These need a little more cooking that the other bits, so I give them a bit longer.


mushrooms/sugar snaps/soft veg


These need less cooking, so bit less time.


bean sprouts 


I like these to be a bit crunchy so add them right at then end and basically just warm through.

If I'm using bigger veg like broccoli/cauliflower then I do them separately to the other veg.  I use a little of the chili/garlic/ginger and fry that for 30 secs, add the broccoli fry for another minute or so just to brown the florets, then add some water, turn down the heat and put on a lid, to steam the broccoli.  Once its done I remove to a separate plate the add back in at the end.

It basically depends on how much you like each veg cooked.  If you prefer your peppers crunchy, put them in nearer the end.