If you use the craquelin, make it in advance as it needs to be frozen for an hour

To make the craquelin

Place everything in a food processor and process until combined (look like crumbs)

Add a teaspoon of water(or vanilla) and process just until everything comes together

Take it out and shape into a ball

Place the ball between two parchment papers and roll out to about 3mm thickness

Cover and freeze for about an hour or until hardened

Once hard enough, cut out round and/or rectangular shapes that matches the choux you are going to use them on

Craquelin disk should be slightly smaller than the piped choux

Once shapes are cut, place them on a parchment and leave in the freezer until needed

To make the choux

Pre heat the oven to 375 °F

Prepare two trays lined with silicon mats (or parchment paper)

Mix flour and salt, give a quick sift and set aside

Place water, milk(if using), butter, sugar in a heavy bottom saucepan and cook over medium heat, stirring until all the butter is melted

Then bring the mixture to a slow boil

Take it off the heat and add all the flour in one go and mix thoroughly with a spatula of a wooden spoon

Keep mixing until it becomes a paste

Place back on medium heat and cook the paste stirring for about 5-8 minutes

The mixture will start to come together and the bottom of the saucepan will start to catch slightly

Check the images in the post above to know when to stop cooking

Once cooked, take the pastry off the heat and let it cool down until it reaches blood temperature (or slightly warm to the touch)

While the pastry cools down, prepare the eggs. Break 4 eggs into a jar and give a quick whisk to break the yolks

Once the paste is cold enough, place it in the bowl of a stand mixer fitted with paddle attachment

Start mixing the dough on medium speed and while adding a little egg mixture at a time

Mix till the eggs are cleared before adding anymore

Scrape the bowl constantly and keep mixing on medium speed

Once the dough start to get smoother stop adding eggs and check the consistency

Keep adding eggs a tablespoon at a time and mix until the dough becomes silky (shiny) and smooth yet hold it's shape

Check the images in the post above to see what this consistency look like

It is crucial to get this right. If you add too much eggs, the mixture will be way too runny and difficult to fix

If you accidentally ended up with a runny batter, check the notes section to see how to fix it

Once you are happy with the choux batter now it is time to pipe

If you are lining the tray with parchment, stick the paper to the tray using a bit of choux pastry itself. So the paper won't move when you pipe

Use a (17mm) round tip or the .56" French tip depending on what you are intending to make

Once the piping bag is fitted with the nozzle, fill halfway with the choux batter

Pipe the shape you want (choux buns or eclairs)

Leave at least 1.5 inch space around as they will expand

If using craquelin, place the disks on the piped choux (check images in the post above)

Place the tray in the center of the oven and quickly close the door

Let these bake for 20 - 25 minutes (or until visibly golden brown

Do not open the door before this time, as it will cause the pastry to collapse

At the 25 minute mark, quickly prick the choux shells with a tooth pick or a cake tester in a few places

This will help the steam to escape allowing the shells to dry out faster

Reduce the temperature to 350 °F and let the shells bake for a further 20 minutes or until they are completely dried out

They will feel firm and very light to the touch and will sound hollow when tapped. If not, leave them for longer

Once done, remove the tray and place in a warm draft-free place (on the stove is best) to cool down slowly

Cooling these too faster will sometimes cause them to collapse

If you are baking two batches, preheat the oven again, while you pipe the rest of the batter

Once all the shells are baked, let them cool completely before filling them or decorating them

Unfilled shells can be frozen for several weeks. Simply place cooled shells in an air-tight container and freeze.