First put your mixing bowl and beater hook in freezer for around 1 hour.
Put your whipping cream in fridge overnight so it gets nice and cold.
Take gelatin and cold water in a bowl, soak the gelatin for 5 mins. Now take it in a sauce pan and heat on a low heat till it gets disolved, set aside so it gets to room temp.
Now take your bowl out and add in cream in it, add in sugar and vanilla. Use your beater to whip this till it is creamy.
Now add in cooled gelatin liquid and continue beating till it gets thick and forms stiff peaks.
Refrigerate until use.
Notes
1)The key for perfect whipped cream is make sure the cream, bowl and the beater which you use has to be cold.2)I used non dairy whipped topping. So i didn't add sugar to it. If you use normal fresh use, add sugar and vanilla in it.3)Dont add too much gelatin, it will spoil the taste.4)You can add agar agar instead of gelatin as well.5)Dont over whip the cream after you get stiff peaks, if you over whip then it will turn into butter.