01 -
Using a stand mixer fitted with paddle attachment, cream softened butter with white and brown sugars on medium speed until fluffy and smooth, approximately 3 minutes.
02 -
Incorporate egg and vanilla extract at low speed until combined, then increase to medium-high for one minute to fully integrate.
03 -
Scrape down bowl sides if necessary. Add baking soda, salt, and cornflour first, mixing for 30 seconds. Gradually incorporate flour about 125g at a time until completely combined.
04 -
Fold in chopped chocolate chunks using a spatula, or mix on low speed until evenly distributed throughout dough.
05 -
Preheat oven to 175°C (350°F). Line a baking sheet with parchment paper.
06 -
Using a serrated knife, slice croissants along one side to create a book-like opening, being careful not to cut completely through. Place on prepared baking sheet.
07 -
Measure approximately 120g of cookie dough for each croissant. Spread a thin, even layer inside each opened croissant before gently closing.
08 -
With remaining portion of allocated dough, form flattened pieces and place on outer tops of croissants at both ends. Continue until all croissants are filled and topped.
09 -
Bake the filled croissants for 10-12 minutes, until cookie dough turns light golden. Avoid overbaking.
10 -
Remove from oven and allow to cool slightly before serving warm.