Preheat the oven to 375°F (190°C). Line two baking sheets with parchment paper.
In a medium bowl, whisk together the all-purpose flour, baking soda, and salt. Set aside.
In a large bowl, using an electric mixer, beat the softened unsalted butter, granulated sugar, and light brown sugar until creamy and smooth, about 2 minutes.
Add the vanilla extract and eggs one at a time, beating well after each addition.
Gradually add the flour mixture to the wet ingredients, mixing on low speed until just combined.
Stir in the semisweet chocolate chips evenly.
Using a tablespoon or cookie scoop, drop rounded dough balls onto the prepared baking sheets about 2 inches apart.
Sprinkle the top of each cookie dough ball with red and green sanding sugar to create a festive Christmas look.
Bake in the preheated oven for 10 to 12 minutes, or until the edges are lightly golden but the centers remain soft.
Remove from the oven and allow the cookies to cool on the baking sheets for 5 minutes before transferring them to wire racks to cool completely.