1pre-heat oven to 450 degrees:
Combine water,butter and salt and bring to a boil. Remove from heat,add flour all at once. Stir vigorously until the mixture leaves the sides of pan and forms a ball around the spoon.
2If a ball does not form almost immediately,hold the pan over low heat and beat vigorously a few seconds.
3Cool slightly. Add eggs one at a time, beating until the mixture is smooth and glossy:DO THIS AFTER EACH EGG ADDITION.
4Drop by rounded spoonfuls onto a greashed baking sheet,leaving 2 inches between the puffs to provide spreading. Bake 15 minutes Then reduce oven temperature to 350 degrees and bake another 30 minutes.
5Cool. You can either cut tops off puffs to add cream or insert cream with decorators pastry bag with decorating tip.
Mix sugar, corn starch and yolks in saucepan. Scald(or boil) your milk and pour it over yolk mixture, stir rapidly with whisk. Cook over low heat DON'T LET THIS PART BOIL. when it has become thick remove from heat. Cool slightly before putting inside puffs.