Prepare the Black Sapote Pulp. Scoop out the flesh from the ripe black sapotes. Discard the seeds and skin. Place the pulp in a blender or food processor and blend until smooth.
Combine the Ingredients. In a large mixing bowl, whisk together the heavy cream, whole milk, sugar, vanilla extract, and a pinch of salt until the sugar is fully dissolved. If you want a richer chocolate flavor, add the dark cocoa powder and whisk until well combined.
Add the Black Sapote Pulp. Stir the blended black sapote pulp into the cream mixture until thoroughly combined.
Chill the Mixture. Cover the bowl with plastic wrap and refrigerate the mixture for at least 2 hours, or until it is thoroughly chilled. This step is crucial for ensuring a smooth and creamy ice cream texture.
Churn the Ice Cream. Pour the chilled mixture into an ice cream maker and churn according to the manufacturer’s instructions. This typically takes about 20-30 minutes. The ice cream should have a soft, creamy consistency when done.
Freeze the Ice Cream. Transfer the churned ice cream to an airtight container. Cover the surface with plastic wrap to prevent ice crystals from forming, then seal with the lid. Freeze for at least 4 hours, or until the ice cream is firm.