*Make Banana Pastry Cream prior to baking pastry.
Preheat oven to 425 F and line a baking tray with a silicone mat or parchment paper.
In a medium sauce pan on medium-high heat, add milk, water, butter, sugar, and salt.
Heat until butter is melted, stirring with a rubber spatula.
Once the butter is melted, turn temperature to a medium-low heat.
Add all the flour at once, whisk quickly to incorporate and make smooth.
Use the spatula to press and fold the batter as it firms.
This should slightly dry the mixture, cooking the flour. (about 1 minute)
Remove from heat and transfer to bowl of stand mixer with paddle attachment.
Turn mixer on to a medium low speed and let some of the hot air work out of the dough. (30 seconds) Let stand and cool for 3-4 minutes.
Turn mixer back onto medium speed and add one egg at a time. Stopping to scrape sides and bottom of bowl between each egg.
Don’t over beat the dough. It will curdled at first, but soon turns into a nice uniform shiny consistency.
You will know its ready, when you turn off the mixer and lift the paddle. If the dough hangs from the paddle without dripping off right away its done. Should hang from paddle in a 'V' shape.
Transfer batter to a pastry bag fitted with a ½-inch round piping tip.
Pipe the batter into 1 inch wide rounds on the prepared baking tray. Gently tap down any peaks with a wet finger tip.
Bake for 15 minutes. Then reduce heat to 350 F for an additional 15 minutes.
Remove tray from the oven and carefully lift each puffed shell and place on cooling rack. Cut a small slit in the side of each puff to release steam. Let cool completely before filling.