While the cake cools, prepare the cream for the filling. Soak gelatin in cold water. Stir Raspberry Jelly Extra in metal bowl until smooth. Whisk whipping cream until stiff. Squeeze water out of gelatin and put gelatin into a ladle. Pour over hot water and stir until gelatin has dissolved. Slowly add liquid gelatin to the almost stiff cream. Add the lemon juice. Fold cream carefully into the preserve. Carefully stir raspberries into cream.