Blend strawberries into puree and set aside. In a bowl, add in egg yolks, corn starch, sugar, vanilla extract and pinch of salt. Whisk until the mixture turns pale. Set aside.
Pour milk into a pot and heat until it starts to simmer. Take ½ cup of the hot milk and slowly pour in the yolk mixture while whisking it.
Now pour the whole thing into the pot, together with strawberry puree and cook on medium heat until thickened. Whisk continuously.
Once thickened, sift the custard into a bowl. Place cling film on its surface, covering all. Leave to cool at room temperature and then chill in the fridge for 4 hours.
Add butter and sugar into a bowl and mix them together using a spatula. Then add in flour and mix everything well. Form into a flat disk.
Place it between two baking sheets and roll it into ⅛ inch (3 mm) thickness. Place in the freezer for 30 minutes.
The Cream Puffs
Into a small pot, add in butter, water, sugar, salt and bring it to a boil and until the butter has melted. Remove from the stove.
Add flour all at once and immediately mix everything using a wooden spoon. Bring the pot back to the stove and continue cooking on medium heat until everything comes together into a ball. Remove from the stove and leave the dough to cool for 10 minutes.
Now add in egg and mix everything until smooth. Put the batter into a piping bag and pipe on a baking tray with baking sheet. Make sure to leave 2 inch (5 cm) space between them.
Take out craquelin from the freezer and cut out into circles using a cookie cutter. Place on top of piped dough.
Bake in a preheated oven, fan forced at 400ºF (200ºC) for 20 minutes. Cool completely on a rack.
Whisk chilled custard until smooth, set aside. In another bowl, whisk whipping cream until stiff peaks. Add into custard bowl and gently fold everything together.
Put mixture in a piping bag with a small round nozzle. Gently poke a hole at the bottom of a cream puff and pipe the filling in. Continue with the rest.
Note: I would recommend you to make the custard cream filling and have it chilling in the fridge for a while to make piping easier.
How To Serve
These cream puffs are best served immediately after piping the filling in. If you leave them too long, they will absorb the humidity of the filling and start losing the crunchiness of the craquelin.
Empty cream puffs are great on the day of baking. The craquelin will not be crunchy the next day.
How To Store
Keep empty cream puffs in air tight container at room temperature.
How To Get It Right
Please refer to my post above where I wrote some tips on how to make them without any problems.