Cream the soft butter, light brown sugar, and granulated sugar in a large bowl. Add the egg and vanilla extract and cream again.1 ¼ sticks unsalted butter/ 150 g + ⅔ cup light brown sugar / 130 g + ⅔ cup granulated sugar / 130 g + 1 egg + 1 teaspoon vanilla extract
Mix flour, baking powder, cinnamon, and salt in another bowl. Sift them over the butter mixture, add 1 tablespoon of water, and mix.1 ½ cups all-purpose flour / 200 g + 1 ¼ teaspoons baking powder + 1 teaspoon cinnamon + 1 pinch salt + 1 tablespoon water
Add the chocolate (chips or chopped) and the chopped walnuts and fold them into the dough using a spoon or your hand. Make sure that they are evenly distributed in the dough.1 ½ cups white chocolate / 250 g + ¾ cup walnuts / 110 g
Chill: Wrap the dough in plastic wrap and refrigerate it for 1 hour.
Preheat the oven to 360°F/180°C (fan-assisted oven 320°F/160°C). Line two baking sheets with parchment paper.
Form the dough balls and place them on the prepared baking sheets. I had 44 dough balls about the size of a large cherry, each weighing about 0.7-0.8 oz/ 20-22 g. Place them on the prepared baking sheets, leaving enough space between them as they will spread (Note 4).
Bake the cookies for 10-12 minutes until golden brown around the edges. Remove them from the oven and let them rest on the trays for about 10 minutes to firm up (Note 5).
Transfer them to wire racks to cool completely.
Glaze:
Mix the confectioners’ sugar with ½ tablespoon water and stir well. Add a few drops more water at a time until you reach the desired consistency; the paste should be thick yet pourable.1 cup confectioners’ sugar/ 125 g + ½ - 1 tablespoon water
Glaze the cookies using a teaspoon. Let the glaze set before transferring the chocolate chip walnut cookies to an airtight container.
Notes
Baking: You will need at least two baking sheets to make things easy. If possible, a fan-assisted oven is preferable, allowing you to bake two batches of cookies simultaneously. If you only have one or two baking trays, always let the tray cool completely before placing the next batch of cookie dough balls on it. If the tray is hot, the ingredients in the dough will start to melt before they can start baking.
Measuring ingredients: I always recommend using a digital kitchen scale in baking; it guarantees the best results. I’ve also tested this recipe using cups, but the metric measurements are always more reliable, especially regarding flour.
Chocolate: You can use white chocolate chips or chunks, if available. Otherwise, chop a bar of white chocolate. Sub white chocolate with any other chocolate you like (milk, semi-sweet, dark).
Refrigeration: Keep the dough that is still waiting to be baked refrigerated. You can form all the balls at once and keep them in the fridge until it’s their turn to be baked.
Let the baking sheets cool before placing the next cookie dough on them.