Preheat the oven to 400°F. Line a baking sheet with parchment paper or a silicone baking mat. Set aside.
In a large bowl, combine the dry ingredients: all purpose flour, cake flour, corn starch, baking soda, baking powder and salt. Set aside.
1 1/4 cup all purpose flour, 3/4 cup cake flour, 1 tsp. cornstarch, 1/2 tsp. baking soda, 1/2 tsp. baking powder, 1/2 tsp. salt
Place the cubed butter and sugars into the bowl of a stand mixture and secure the paddle attachment. Turn the mixer on and cream until smooth, about 1-2 minutes.
8 Tbsp. unsalted butter, cold, cut into cubes, 1/2 cup brown sugar, packed (light or dark), 1/4 cup sugar
Add in the eggs, egg yolks, peppermint and vanilla extracts and blend until mixed. Use a rubber spatula to knock off mixture if any is sticking to the sides of the bowl and mix again.
1 large egg, 1 large egg yolk, 1 tsp. peppermint extract, 1 tsp. vanilla extract
Gradually add in the dry ingredients, about 1/4 cup at a time. Mix until incorporated, then add in 1 cup chocolate chips and chopped peppermint bark. (Note: You can reserve a few peppermint bark pieces for garnishing once cookies have baked).
1 1/2 cup white chocolate chips, divided, 7 oz. peppermint bark, frozen & chopped (I use Ghirardelli)
Roll cookie dough into 6 large balls, or smaller if preferred (adjust baking time as needed for smaller cookies).
Place on baking sheet & bake cookies for ~10-11 minutes. Cool cookies completely.
Microwave remaining 1/2 cup white chocolate in a microwave safe bowl in 30 second increments until smooth and drizzle over cooled cookies. Garnish with crushed candy canes if desired and enjoy!
crushed candy canes for garnish