- Preheat the oven to 325°F (160°C) and line 2 baking trays with parchment paper.
- In a large mixing bowl, cream the butter and both sugars by hand or using electric beaters on medium. Beat in the egg yolks, vanilla, and lemon zest, then the lemon juice. (If the mixture looks a little curdled, sift 1/2 cup/75g of the flour into the mixture to smooth it out.) Stir in the melted white chocolate.
- In a separate bowl, sift the flour, cornstarch, baking soda and baking powder together. Add all at once to the butter mixture and mix by hand or on low speed until combined (the dough will be soft but manageable for scooping).
- Use a small ice cream scoop or 2 teaspoons to shape the dough into balls. Roll the balls in the sugar to coat thoroughly and arrange them on the baking trays, 2 inches (5 cm) apart. Press down gently on them with the palm of your hand.
- Bake for 12 to 14 minutes, until a cookie can be gently lifted from the tray. Carefully smack the tray down on the counter to deflate the cookies (for the crinkle effect). Let cool on the tray for 5 minutes, then transfer to a wire rack to cool completely.
You can store these baked cookies for up to 5 days in an airtight container at room temperature. Or scoop the dough and freeze the cookies on a baking tray without rolling them in sugar first. Once frozen, pack them into an airtight container and store for up to 3 months. To bake, let the frozen cookies thaw on a baking tray for about 20 minutes before rolling them in sugar and putting them in the oven.
Recipe from Set for the Holidays with Anna Olson, Appetite by Random House, 2018