Heat the oven to 428°F (220°C) and oil 2 baking dishes. Boil the water and put in the butter and a pinch of salt. Once the butter melts, remove from the heat and pour in all of the flour at once. Stir intensely until the dough begins to separate from the walls of the pot.
Add the whipped eggs and knead well. Pour the mixture into a pastry bag. Spray out 12 eclairs into the baking dishes and smear on some whipped egg on them. Bake for 10 min, then lower the heat to 356°F (180°C) and bake for another 20 min.
Turn off the oven, open the door and leave the cream puffs inside for 10 min. Melt the chocolate with the sugar in a water bath. Open the cream puffs slightly and fill them with the cream, pour on the chocolate sauce and serve.