For this recipe, we're looking for just barely ripe, firm avocados. So, look for an avocado that's firm to the touch (not squishy but a little bit of give is fine). The color should be purple-ish black with still some green mixed in. One of our favorite ways to check if the avocado's overripe is by simply pulling off the little stem on top. If it's dark under the stem, it's overripe. If it's green, it's perfect!