Guacamole, the fresh green yumminess, can easily turn into an unattractive shade of brown. If by chance, you have any guacamole after serving it (this is a rarity in our house – my middle child is a guacamole-eating monster!) the best way to store it is by placing it in a small bowl or other glass container and covering it with plastic wrap. The key is to not allow any air to get between the wrap and the guac. Smush the plastic wrap and then let the edges cling to the sides. Refrigerate.