Lots of recipes call for waiting for the water to come "to a boil." However I have never been sure when that is. From my viewpoint it could be at three different points:
- First start to see small air bubbles coming up from the bottom of the pan
- When the surface of the water is noticeably disturbed by the bubbles
- When it is a full on raging torrent of activity
Depending on the amount of water used, these three points could be several minutes apart from each other, which will affect the cooking time.