My lunch consisted of homemade guacamole and a Rolling Rock.
There's a lot of theories about the prevention (or at least the slowing down) of avocados oxidizing and turning brown quickly. Like apples, you can postpone the browning by adding an acid (in this case, a lime). There's also an urban legend about using the avocado pit to slow the browning as well. Either way, just to be safe, I used both.
Avocado (1 large, or 2 medium, ripe)
1 diced Roma Tomato (I like the Roma for this because they're firm, and the juices don't run out)
1/4 diced White Onion