Preheat the oven to 350 degrees. Line a baking sheet with parchment paper or a silpat mat.
Combine the flour, baking soda, and salt together in a small bowl; mix until well combined.
In a separate large bowl, beat the butter, brown sugar, and white sugar together until creamy and smooth, making sure to scrape down the sides of the bowl as needed, about 1-2 minutes.
Add the egg and vanilla extract then beat until well combined.
Slowly add the flour mixture to the butter mixture until just combined.
Add all but 3 tbsp of the Andes mint baking chips along with 1/4 cup of the dark chocolate chips to the batter; gently stir to combine.
Scoop spoonfuls (about 1 ½ tbsp) of the dough onto the baking sheet placing them 2 inches apart. Place into the oven and bake for 7-9 minutes, or until set.
Remove from the oven and immediately sprinkle a bit of the remaining Andes mint baking chips on top of each cookie as well as a couple of the remaining chocolate chips - don't overload them but this will make the cookies look extra pretty.
Allow them to set for 5 minutes before moving them to a wire rack to finish cooling.