Prepare the choux pastry as described in the recipe linked here:https://trophyhusbandbakeshop.com/choux-pastry-recipe/ Transfer the mixture to a piping bag with a 1-½" french star tip. Shake the bag a few times to get any air bubbles out and twist the bag to close.
Place the tip of the piping bag on the parchment paper at a 45 degree angle and without lifting the tip off of the parchment, pipe a 4-5" long log. Twist the tip when you want to stop piping for a clean break. Dip your fingers in water and press the rough edge of the dough back in for a clean end. Repeat for the rest of your eclairs.
Dust the tops of your eclairs with a bit of powdered sugar or spray them with a bit of cooking spray like pam.
Bake for 25 minutes at 375. After 25 minutes poke a hole in the ends of all of the eclairs, rotate the trays from the bottom to the top racks and bake for another 5 minutes
After 5 minutes, turn the oven off and leave the eclairs inside to cool for 15-20 minutes. Prop the oven door open to help them cool slowly. Remove the pastry cream from the fridge so it can start warming up.
Remove the eclairs from the oven and using a small paring knife, poke three holes in the bottom of each eclair to allow steam to escape and to help with filling later. Let the eclairs cool completely on the baking trays.
Take the bag of pastry cream and insert the tip into the bottom of one of the eclairs and squeeze the bag to fill. The eclairs should be sufficiently filled but not so much that they're bursting. Repeat with the rest of the eclairs.