Over on The Rachael Ray show, we found a tip that will be super helpful to all of you avocado and guacamole lovers out there. When you cut an avocado in half or you have a bowl of unfinished guacamole, simply spray the open (air-exposed) side with a bit of veggie spray. Then press some plastic wrap right against it to keep air out and keep your avocado fresher for longer!
Source: The Rachael Ray Show