For pate choux:

Preheat oven to 375.
Bring water, butter, salt and sugar to boil.
Dump in flour, stir to paste and continue over heat until it starts to stick to bottom of pan.
Cool slightly.
Dump in mixer and beat in eggs.
Whip to thin batter.

Pipe or shape on parchment to 4 - 6 inch tubes.
Increase oven to 425, bake for 15 minutes.
Reduce to 350 and bake another 10.
Pierce end to let steam escape. Cool.

Fill with pastry cream and dip top in chocolate icing.