Soften the gelatin with 100 ml of hot water( keep the bowl warm in the double boiler).
In a small saucepan combine the 300 ml water and sugar.
Place over medium high heat until the mixture reaches 116 centigrade.(use the candy thermometer)
Once the mixture reaches this temperature remove from heat.
Pour the sugar mixture in to the gelatin mixture and using an electric mixture, beat on high speed for 10 minutes and add vanilla and beat for one minute.
Pour the mixture into greased molds and leave for at least 6 hours to set.