This is a wonderful way to cook cauliflower – tangy and lip smacking! You can get green mango powder in any Asian grocer where it is often sold as amchoor. It is what Indians use to bring sharpness to their dishes. If you can’t get hold of it, blend the flesh of an underripe mango with a little lemon juice and use that instead. Remember, don’t leave the cauliflower florets too big as they take longer to cook.