Preheat oven to 400 degrees.
Heat water and butter to a rolling boil in a saucepan. Stir in flour all at once. Stir vigorously with a wooden spoon over low heat until mixture no longer sticks to pan and forms into a ball. Remove from heat. Using an electric mixer, beat eggs in thoroughly, one by one. Beat mixture until smooth. Spoon cream puff mixture into a pastry bag fitted with a plain tube and pipe the equivalent of a tablespoon onto ungreased baking sheet leaving 3 inches apart.
Bake for 15 minutes. Reduce the oven to 350 degrees and continue baking until puffed, golden brown and dry.
FILLING:
Whip the cream with sugar and instant vanilla pudding until stiff. Fill the puffs with cream using a pastry bag fitted with a small plain tube. Other fillings can be used (ice cream, chocolate or vanilla pudding).