Companies have gotten better with preserving individual packages of guacamole (like Wholly Guacamole ... pretty fast to whip ...

It's not my favorite to eat with chips, which are already salty ... that's carried at Costco is Good Foods organic guacamole. Rather than individual cups, these are sized to share at 10 ounces ...

In a large bowl, mix onion and lime juice. Let sit 5 minutes. Add the avocado, mayonnaise, salt and cilantro, and mix gently to incorporate. Serve immediately with salty tortilla chips.