When water boils, it produces bubbles. These bubbles rise to the surface and pop, causing the water to splash out of the pot. Easy Mac boil over happens when there is too much water in the pot and not enough space for the bubbles to escape. The bubbles build up pressure and eventually cause the water to overflow.
There are a few things you can do to prevent Easy Mac boil over. First, make sure you use a pot that is big enough for the amount of water you're boiling. Second, don't add too much water - only add as much as you need. And finally, if you see the water starting to boil over, turn off the heat immediately and let the pot cool down before continuing.