In a saucepan, heat 200 ml of fresh cream on low flame until it starts to simmer. Do not let it boil.
In a separate bowl, mix 100 grams of cocoa powder and 200 grams of sugar.
Slowly add the cocoa-sugar mixture to the simmering cream, stirring continuously to avoid lumps.
Cook the mixture on low heat for 5-7 minutes until it thickens, then remove from heat and let it cool.
In a large bowl, whisk 500 ml of chilled heavy cream until soft peaks form.
Gently fold the cooled chocolate fudge mixture into the whipped cream until well combined.
Pour the mixture into an airtight container and freeze for at least 6-8 hours or overnight for best results.
Scoop out the fudge ice cream and serve.