Traditional Crispy Walnut Cookies

Spread 25g walnuts on a pan and place in the middle rack of an oven preheated to 180°C. Bake with top and bottom heat (no fan) for 8 minutes until light golden and fragrant. Remove and leave on the pan to cool completely.

Transfer the cooled walnuts onto a cutting board and chop them into small uneven pieces with a knife for a better layered texture.

Set a fine sieve over a bowl. Sift 110g cake flour, 1g baking powder, and 1g baking soda together into the bowl, then whisk thoroughly to distribute evenly.

Place 65g room-temperature softened unsalted butter in a bowl. Ensure it leaves a finger indent without being sticky or melted, then use an electric mixer on low speed to spread it into a smooth paste.

Sift 50g caster sugar and 1g salt into the butter. Stir briefly by hand to prevent sugar from flying out, then beat on medium speed for 3 minutes. Scrape down the sides and bottom of the bowl midway, and continue beating until pale, fluffy, and stiff peaks form.

Crack 1 egg, separate the yolk and whisk it. Measure and set aside 8g of egg yolk for brushing later. Add egg white back to the remaining yolk until the mixture weighs exactly 15g, then whisk thoroughly with a fork.

Pour the 15g egg liquid into the beaten butter mixture. Mix on low speed with the electric mixer until completely absorbed and smooth with no liquid separation.

Pour the sifted flour mixture into the butter bowl. Gently fold in with a silicone spatula until just a little dry flour remains, then add the 25g chopped walnuts and fold lightly to combine.

When dry flour disappears and the dough feels sticky, switch to the 'spread method'. Use a spatula to spread and press the dough gently against the bowl, targeting different areas each time, until a smooth, soft, and non-sticky dough ball forms.

Weigh and divide the dough evenly into 10 portions (about 25g each). Roll each portion into a smooth ball between your palms, place on a baking mat-lined tray, flatten slightly, and use your index finger to poke a shallow indent in the center. Leave space between cookies.

Stir the reserved 8g egg yolk with a soft pastry brush and brush a thin layer evenly over the surface and shallow indent of each cookie. Then, sprinkle 1g black sesame seeds into the center indent of each cookie.

Place the tray with shaped cookies into the middle rack of the preheated 180°C oven. Bake with top and bottom heat (no fan) for 20 minutes until expanded, golden brown, and showcasing signature crack patterns.

Wearing oven mitts, remove the baking sheet from the oven. Allow the walnut cookies to cool on the tray until warm/cool to the touch before moving them onto a plate to serve.