Dry roast the cashews in the oven for 5 minutes turning the nuts over once. Place them in a food processor and processing slowly adding the soy milk until smooth. Remove the skin and seeds from the custard apple and add to the food processor. Blend until smooth.
Remove the core from the apples and cut into chunks. Add the water and star anise and under a medium heat slowly bring the water to boil. Reduce the heat to simmer, partially cover the pan and cook until the apples are tender. Remove the star anise. Serve the apples with the custard.
Note: If you want to accelerate the ripening process of your Custard apples, simply put the fruit into a brown paper bag with a banana and leave it on the kitchen bench. The fruit will not ripen below 14 degrees Celsius.