Store leftover mini avocado toast in an airtight container in the fridge for up to 2 days. Honestly, this caprese avocado toast does not save well and it is best to make it right before you are ready to serve. The avocado gets pretty funky after a day or two, so you won't want to eat on it for days. Of course, you can prep all the ingredients and store them separate and assemble before you are ready to eat them. Just slice the avocado and add when you are ready to devour. Storing the toast this way gives it a longer life of about 4 days.