Set ice in your freezer, you will need 2 trays for this
Chill the whipping cream and condensed milk overnight
In a bowl add 1 can of chilled condensed milk and vanilla essence
Sift 50gms of cocoa powder
Using the cutting and folding method, mix thoroughly
You need 2 mixing bowls for this
Keep both bowls in the freezer for 15-20 minutes and whisking attachment
Add ice in the deeper bowl and place the 2nd bowl on top
Add 400 grams of chilled cream and add 2 tablespoons cream of tartar
Whip in 3 minute intervals, add mixture 1/4 cup at a time
Add mixture, till it is over.
Continuously whip for about 3-4 minutes, it should flow like ribbons.
The consistency will be really creamy and you should see soft peaks.
Freeze for a minimum of 6 hours.