Biscoff Chocolate Chip Cookies

In a large bowl using a hand mixer or in the bowl of a stand mixer using the whisk attachment, beat butter for 1 minute on medium speed until completely smooth and creamy. Add sugars and beat on medium-high speed until fluffy and light in colour. Beat in egg, egg yolk, and vanilla on high speed. Scrape down sides and bottom of bowl as needed. On high speed, beat in Biscoff spread. In a separate bowl, whisk flour, bicarbonate of soda, cinnamon, cornflour, and salt together until combined. On low speed, slowly mix into wet ingredients until combined. Switch to high speed and beat in chocolate chips (the cookie dough will be a little sticky). Cover dough tightly with aluminium foil or cling film and refrigerate, 3 hours, or up to 3 days. Remove cookie dough from refrigerator and allow to sit at room temperature for 20 minutes (if cookie dough chilled longer than 3 hours, let sit at room temperature for about 30 minutes). Preheat oven to 180°C (160ºC fan) and line two large baking trays with parchment paper or silicone baking mats. Scoop and roll pieces of dough into balls, 1 1/2 tablespoons at a time, and place on baking trays. Bake cookies for 9 to 10 minutes. Be sure to rotate pan once or twice during bake time. Baked cookies will look extremely soft in centres when removed from oven. Allow to cool for 5 minutes on tray, then transfer to cooling rack to cool completely.