1
Line two baking trays with baking paper.
2
Combine the butter, cream cheese, both sugars, baking soda, salt, and vanilla extract in a large mixing bowl.
3
Mix until the mixture is creamy, uniform in color, and clings to the side of the bowl.
4
Scrape down the bowl sides with a spatula and add the egg. Mix to incorporate.
6
Add the egg yolk, red food colouring, flour, and cocoa powder. Mix gently until the dry ingredients are just absorbed.
7
Add the chocolate chips to the dough, reserving a handful for topping, and mix until evenly distributed.
8
Wet your hands, then lightly dry them with a paper towel. Roll out 1-inch balls of dough and place them on the prepared baking trays.
9
Bake the cookies on one baking tray for 11 to 13 minutes, or until the edges are dry and set.
10
Remove cookies from the oven. Press several white chips into the tops of the warm, puffy cookies.
11
Cool the cookies on the baking sheet for 5 minutes, then transfer them to a wire cooling rack.
12
Repeat the process with the other baking tray.