Chocolate filling - Boil fresh milk, cocoa mixture, sugar and agar agar powder over medium heat, then add coffee powder into it and stir well. Off heat and add the chocolate into the hot milk. Stir the mixture till chocolate dissolved and smooth. Then pour evenly into 8 muffin cups and place into refrigerator to set for about 15 minutes.

Remove chocolate filling jelly from cup, using a sharp knife to scrape the jelly on both sides, this will makes the jelly stick together. Set aside for later use.

Mooncake outer layer - Combine cocoa powder and 50ml fresh milk together, set aside.

In a pot, combine fresh milk, cocoa mixture, sugar and agar agar powder over medium heat. Stirring continuously to boil with a hand whisk. Off heat and add Nutella in 2-3 batches. Stir till Nutella completely dissolved and smooth.

Pour Nutella liquid mixture mixture into mooncake mould about 1/2 cm high and let it cool to semi-set about 30 seconds to 1 minute. Place the chocolate filling jelly on top. Warm up the remaining Nutella liquid mixture and pour over the chocolate filling jelly to full.

Allow jelly to set completely and keep refrigerated until ready to serve.