Preheat the oven to 350 degrees.
Line 2 baking sheets with parchment paper.
In a medium bowl, whisk together the flour, baking soda, and salt.
Beat together the butter, white sugar, and brown until light and creamy.
Add in the egg until just combined.
Add in the peppermint and vanilla extract until just combined.
Add in the dry ingredients and mix until just a few streaks are left.
Sprinkle in 1/2 cup crushed peppermint and the peppermint white chocolate chips stirring to combine.
Add 1/2 cup of the remaining crushed peppermint into a small bowl.
Scoop out 2 tbsp sized dough balls and roll in crushed peppermint before placing onto the parchment lined baking sheets.
Bake for 7-10 minutes until corners are just slightly darker than the center of the cookie.
Allow to cool on a wire rack.