Found this on foodpusher.com
unfalvored gelatin powder
pinch of salt
1In bowl sprinkle gelatin over cold water. Scald 2 tablespoons of whipping cream and pour over gelatin. Stir until dissolved.
2Refrigerate about 15 minutes. Then whisk until smooth.
3Mix remaining cream, sugar and salt. Mix in smooth gelatin mixture stopping to scrape bowl twice.
(Fills and frosts top of 8 or 9 inch layer cake.)