2 tsp powdered unflavored gelatin2 T water
2 C heavy cream
4 T sugar (more or less to taste)
2 tsp vanilla extract (optional)
Put the gelatin and water in a small bowl and let sit for about 10 minutes, or until it swells and absorbs the water. Stir in the softened gelatin with a fork to break up the lumps.
Add 1/4 C plus 2 T of the cream to the gelatin mixture and put the bowl over a saucepan or simmering water. Stir the mixture with a rubber spatula until it is smooth, then remove from heat. Don't heat it any more than is needed to dissolve the gelatin.
Combine the remaining cream with the sugar and vanilla and beat to medium peaks. Turn the mixer to low speed and pour in the gelatin mixture in a steady stream, avoiding the whisk and sides of the bowl. Continue beating just long enough to incorporate the gelatin.
Whipping cream may be spread or piped.
**Place the whipping cream in the freezer for 5 minutes before mixing. This will prevent it from beginning to separate into butter in a warm kitchen.
From: Baking by James Peterson