Preheat oven to 450˚F and line a baking sheet with a silicone mat, set aside.
In a medium saucepan, combine water, milk, butter, sugar and salt. Bring to a boil over medium heat then remove from heat and stir in flour all at once with a wooden spoon.
Once flour is incorporated, place back over medium heat for about 2 minutes stirring constantly or until dough comes together into a smooth ball and a thin film forms on the bottom of the pan.
Transfer to a large mixing bowl and beat using an electric hand mixer on medium speed for 1 minute to cool slightly. Add eggs, one at a time, until dough is smooth and forms a thick ribbon when the beater is lifted.
Transfer pastry dough to a piping bag fitted with a 1/2” round tip. Pipe 4” long and keeping them 2" apart.
Bake at 450˚F for 5 minutes. Without opening the oven, reduce to 350˚F and bake for another 20-25 minutes or until golden brown. Prick them to remove air and transfer to wire rack to cool while making the pastry cream.