Preheat your oven to 350°F (175°C) and line a baking sheet with parchment paper.
In a small bowl, whisk together the flour, baking soda, and salt. Set aside.
In a large mixing bowl, cream together the softened butter, granulated sugar, and brown sugar until light and fluffy.
Add the egg yolk and vanilla extract to the butter mixture, mixing until well combined.
Gradually add the dry ingredients to the wet ingredients, stirring until just combined.
Fold in the mini chocolate chips.
Using a teaspoon, scoop small amounts of dough and roll them into balls. Place them on the prepared baking sheet, spacing them about 2 inches apart.
Bake for 8-10 minutes, or until the edges are lightly golden. Remove from the oven and let them cool on the baking sheet for 5 minutes before transferring to a wire rack to cool completely.