I discovered a way to ripen an Avocado, if you buy them still un-ripe.
I bought a bag that stated on it that it was picked, packaged 2 weeks before in Mexico.
Well they were too hard to cut open, so I searched and found suggestions to ripen them, some suggested a few seconds in the microwave, and went on to say that if you put them in an airtight " Tupperware" bowl, and store them in a dark corner they will ripen soon.
I did that, put them in a sealed container, put them in a dark pantry, and a week later I have nice ripened avocados.
I have a pint jar of clean pits , drying out , before I try the idea that Neal posted, to grind them up in a small coffee grinder, will see how that turns out.