In a medium bowl, whisk together the flour, baking soda, cornstarch and salt. Set aside.
In a large bowl, beat together the butter and sugar on high until well mixed (about 1 minute).
Beat the eggs, vanilla extract and cotton candy extract into the butter mixture until well mixed (about 30 seconds).
On a low speed, beat in the dry ingredients. Don’t overmix – just mix until you no longer see dry ingredients that haven’t been mixed in with the wet ingredients.
Separate the cookie dough evenly between two bowls. Color one bowl of dough pink and color the other bowl of dough blue.
Preheat oven to 350 degrees F. Add parchment paper to the baking sheets.
Scoop dough out into one tablespoon scoops. Take a scoop of blue and a scoop of pink and put them together to make a half blue, half pink cookie. Use your hands to roll these together into a round ball, then place them onto a baking sheet.
The cookies can be placed close to each other on the baking sheet in order to chill. Chill the dough for at least an hour before baking.
Line a second baking sheet with parchment paper and take some cookies out of the freezer and place on baking sheet. Cookies should be 2 inches from each other on the baking sheet.
Bake each tray of cookies for 12 minutes or until cookie edges seem set. The middles of cookies will still look slightly wet and that’s okay!
They’ll finish baking on the hot tray when they come out of the oven. After cookies have cooled for 10 minutes, transfer to a wire rack to cool completely.
Notes
Store cookies in a sealed food safe container at room temperature for 5-7 days or in freezer for up to 3 months.