Bring milk, 100 ml water, salt and butter to the boil in a saucepan. Add flour at once and stir with a mixing spoon until the dough separates from the bottom of the pot as a lump and a white layer forms on the bottom. Put the dough into a mixing bowl and immediately stir in 1 egg. Then let the dough cool down for about 10 minutes. Stir in the remaining eggs one by one.
Pour the choux pastry into a piping bag with a large perforated spout. Spray 6 tuffs each onto 2 baking trays lined with baking paper. Fill an ovenproof dish with water and place on the bottom of the oven. Bake the baking trays one after the other in a preheated oven (electric cooker: 225 °C/ convection oven: 200 °C/ gas: level 4) for 20-25 minutes. Remove the finished cream puffs from the oven and cut them open immediately with scissors. Let them cool down. Whip 150 g cream until stiff, briefly stir in liqueur and vanilla sugar. Fill the lower halves of the cream puffs with cream, place the lid on top and chill. Break chocolate into pieces for the sauce.
Let them cool down. Whip 150 g cream until stiff, briefly stir in liqueur and vanilla sugar. Fill the lower halves of the cream puffs with cream, place the lid on top and chill. Break chocolate into pieces for the sauce. Melt with 100 g cream over a warm water bath, stir until smooth. Serve cream puffs with sauce