The instruction

Put your avocado on a baking sheet and wrap it in aluminum foil before placing it in the oven.

Depending on the degree of toughness of the animal, bake for about ten minutes in an oven that has been prepared to one hundred degrees Celsius.

Take the avocado out of the oven, wait for it to cool, and then remove the wrapping. The fruit will be absolutely ripe, firm, and somewhat creamy if all goes according to plan.

As a brief explanation from a scientific standpoint, aluminum foil has a role in preserving the ethylene gas that is generated by the avocado and is responsible for the ripening process.