Dissolve the gelatin in a little cool water and let it swell, then liquefy it in a water bath. Add it to the beaten yoghurt. Add the raspberries, slightly beaten, then the freshly squeezed lemon juice and a little grated lemon rind.
Lastly, add the powdered sugar and mix the products well. Put the mixture into small bowls and leave for at least 4 hours in the refrigerator to gel.
Before serving, submerge briefly in hot water and invert onto suitable plates.