Melt the butter in a heavy pan with the water (190 ml - three quarters cup)and bring to the boil. Remove from the heat. Add the flour and salt beat with a wooden spoon until glossy It should be the consistency to form small balls at this stage. Turn out onto a plate and spread out to cool.
Return to the pan and gradually beat in the eggs.
Fill a bag with the mixture and attach a three-fourths ins plain nozzle. Pipe the choux pastry into small balls on a greased baking sheet. Space them out well apart.
Bake in the oven for 25 mins until well risen and golden brown.
Pierce each one to allow the Steam to escape. Return to the oven for 2 mins then cool on a wire rack.
Filling: Whip half the cream with the milk. Fold in the icing sugar, sugar and the raspberry liqueur. Whip the remaining cream and make a mould in the centre of a serving plate.
With the other half of the cream mixture fill a pastry bag with a star nozzle. Fill each choux bun with it and place them round the cream mould. So that it is completely covered then pipe rosettes between each bun.
For the caramel: Melt the sugar in a saucepan with the water (155 ml- two-thirds cup). Boil until it turns brown and caramelizes. Cool until the caramel begins to thicken but not set.
Pour quickly but gently over the cake. Leave to set and chill for half an hour before serving