1. In a bowl, add egg yolk. Pour the milk into the bowl little by little, and mix. Add sugar and mix.
2. Transfer the milk mix into a small pan and heat it up to 75~80℃ over medium heat, turn the heat to low and simmer for 3min.
3. Add the chocolate into the milk mixture and let it melt completely. Then sift the cocoa powder through a sieve. Mix.
4. Using a fine mesh filter (your usual sieve will do), strain the milk into a heat-safe bowl, then add the glucose powder. Mix well to melt. Let it cool down completely in the water bath.
5. Once the milk mixture is cooled completely, add heavy cream. Mix.
6. Place the mixture into your compressor ice cream maker. Let it run according to manufacturer's instructions. It should take 40~60min, depending on how cold the mixture is. In case of doubt, you should let it run until the mixture turns thick and creamy.
7. Transfer the ice cream to a storage container, and let it freeze until you eat!