For the dough, boil 1/4 litre of water, fat and salt. Add the flour at once and stir in until the dough comes off the bottom of the pot as a lump. Remove the pot from the heat. Knead in the eggs bit by bit.
Let it rest for about half an hour. Pour the dough into a piping bag with star-shaped spout and squirt 8 rosette-shaped heaps onto a baking tray lined with baking paper. Bake in the preheated oven (electric cooker: 200 °C/ gas: level 3) for about 40 minutes.
In the meantime, thaw the raspberries. For the yoghurt cream, whip cream with vanilla sugar and cream firmer until stiff. Fold in yoghurt. Cut off one cap from each of the still warm cream puffs with a pair of scissors and leave to cool.
First cover the lower halves with raspberries (keep some for decoration). Pour yoghurt cream into a piping bag with a star-shaped spout and squirt onto the raspberries. Drizzle a little eggnog over it.
Put the lid on it. Dust with icing sugar. Arrange one cream puff each with some raspberries and lemon balm leaves on a small plate. Makes 8 pieces.