Preheat the oven to 350°F (175°C) and line baking sheets with parchment paper to prevent sticking and ensure golden bottoms.
Whisk flour and baking soda in a small bowl and set aside. Sift flour if it looks clumpy for fluffier dough.
Beat butter, granulated sugar, and brown sugar until light, fluffy, and pale, about 2 to 3 minutes.
Mix in salt, vanilla, and eggs until smooth and creamy.
Add the flour mixture gradually, mixing on low just until combined; stop once flour streaks disappear to avoid tough cookies.
Fold in semisweet chocolate chips, white chocolate chips, and freshly crushed peppermint candies.
Scoop rounded tablespoons of dough onto parchment-lined sheets, spacing 2 inches apart, and bake 10 to 12 minutes until edges are golden and centers look slightly soft.
Cool cookies on the tray for 5 minutes, then transfer to a wire rack to finish setting and stay chewy.